diff --git a/mozilla/content/html/content/src/nsHTMLSharedElement.cpp b/mozilla/content/html/content/src/nsHTMLSharedElement.cpp
new file mode 100644
index 00000000000..39c6252e562
--- /dev/null
+++ b/mozilla/content/html/content/src/nsHTMLSharedElement.cpp
@@ -0,0 +1,433 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: NPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Communicator client code.
+ *
+ * The Initial Developer of the Original Code is 
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1998
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the NPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the NPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+#include "nsIDOMHTMLEmbedElement.h"
+#include "nsIDOMHTMLIsIndexElement.h"
+#include "nsIDOMHTMLParamElement.h"
+#include "nsIDOMHTMLBaseElement.h"
+#include "nsIDOMEventReceiver.h"
+#include "nsIHTMLContent.h"
+#include "nsGenericHTMLElement.h"
+#include "nsHTMLAtoms.h"
+#include "nsHTMLIIDs.h"
+#include "nsIStyleContext.h"
+#include "nsStyleConsts.h"
+#include "nsIPresContext.h"
+#include "nsRuleNode.h"
+#include "nsIHTMLAttributes.h"
+
+
+class nsHTMLSharedLeafElement : public nsGenericHTMLLeafElement,
+                                public nsIDOMHTMLEmbedElement,
+                                public nsIDOMHTMLIsIndexElement,
+                                public nsIDOMHTMLParamElement,
+                                public nsIDOMHTMLBaseElement
+{
+public:
+  nsHTMLSharedLeafElement();
+  virtual ~nsHTMLSharedLeafElement();
+
+  // nsISupports
+  NS_DECL_ISUPPORTS_INHERITED
+
+  // nsIDOMNode
+  NS_FORWARD_NSIDOMNODE_NO_CLONENODE(nsGenericHTMLLeafElement::)
+
+  // nsIDOMElement
+  NS_FORWARD_NSIDOMELEMENT(nsGenericHTMLLeafElement::)
+
+  // nsIDOMHTMLElement
+  NS_FORWARD_NSIDOMHTMLELEMENT(nsGenericHTMLLeafElement::)
+
+  // nsIDOMHTMLEmbedElement
+  NS_DECL_NSIDOMHTMLEMBEDELEMENT
+
+  // nsIDOMHTMLIsIndexElement
+  NS_DECL_NSIDOMHTMLISINDEXELEMENT
+
+  // nsIDOMHTMLParamElement Can't use the macro
+  // NS_DECL_NSIDOMHTMLPARAMELEMENT since some of the methods in
+  // nsIDOMHTMLParamElement clashes with methods in
+  // nsIDOMHTMLEmbedElement
+
+  NS_IMETHOD GetValue(nsAWritableString& aValue);
+  NS_IMETHOD SetValue(const nsAReadableString& aValue);
+  NS_IMETHOD GetValueType(nsAWritableString& aValueType);
+  NS_IMETHOD SetValueType(const nsAReadableString& aValueType);
+
+  // nsIDOMHTMLBaseElement
+  NS_DECL_NSIDOMHTMLBASEELEMENT
+
+  // nsIContent
+  NS_IMETHODIMP_(PRBool) IsContentOfType(PRUint32 aFlags);
+
+  NS_IMETHOD StringToAttribute(nsIAtom* aAttribute,
+                               const nsAReadableString& aValue,
+                               nsHTMLValue& aResult);
+  NS_IMETHOD AttributeToString(nsIAtom* aAttribute,
+                               const nsHTMLValue& aValue,
+                               nsAWritableString& aResult) const;
+  NS_IMETHOD GetAttributeMappingFunction(nsMapRuleToAttributesFunc& aMapRuleFunc) const;
+  NS_IMETHOD GetMappedAttributeImpact(const nsIAtom* aAttribute,
+                                      PRInt32 aModType, PRInt32& aHint) const;
+
+#ifdef DEBUG
+  NS_IMETHOD SizeOf(nsISizeOfHandler* aSizer, PRUint32* aResult) const;
+#endif
+};
+
+nsresult
+NS_NewHTMLSharedLeafElement(nsIHTMLContent** aInstancePtrResult,
+                            nsINodeInfo *aNodeInfo)
+{
+  NS_ENSURE_ARG_POINTER(aInstancePtrResult);
+
+  nsHTMLSharedLeafElement* it = new nsHTMLSharedLeafElement();
+
+  if (!it) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  nsresult rv = it->Init(aNodeInfo);
+
+  if (NS_FAILED(rv)) {
+    delete it;
+
+    return rv;
+  }
+
+  *aInstancePtrResult = NS_STATIC_CAST(nsIHTMLContent *, it);
+  NS_ADDREF(*aInstancePtrResult);
+
+  return NS_OK;
+}
+
+
+nsHTMLSharedLeafElement::nsHTMLSharedLeafElement()
+{
+}
+
+nsHTMLSharedLeafElement::~nsHTMLSharedLeafElement()
+{
+}
+
+
+NS_IMPL_ADDREF_INHERITED(nsHTMLSharedLeafElement, nsGenericElement)
+NS_IMPL_RELEASE_INHERITED(nsHTMLSharedLeafElement, nsGenericElement)
+
+
+// QueryInterface implementation for nsHTMLSharedLeafElement
+NS_HTML_CONTENT_INTERFACE_MAP_AMBIGOUS_BEGIN(nsHTMLSharedLeafElement,
+                                             nsGenericHTMLLeafElement,
+                                             nsIDOMHTMLEmbedElement)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIDOMHTMLElement, nsIDOMHTMLEmbedElement)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLEmbedElement, embed)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLParamElement, param)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLIsIndexElement, isindex)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLBaseElement, base)
+
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLEmbedElement, embed)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLParamElement, param)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLWBRElement, wbr)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLIsIndexElement, isindex)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLBaseElement, base)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLSpacerElement, spacer)
+NS_HTML_CONTENT_INTERFACE_MAP_END
+
+
+nsresult
+nsHTMLSharedLeafElement::CloneNode(PRBool aDeep, nsIDOMNode** aReturn)
+{
+  NS_ENSURE_ARG_POINTER(aReturn);
+  *aReturn = nsnull;
+
+  nsHTMLSharedLeafElement* it = new nsHTMLSharedLeafElement();
+
+  if (!it) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  nsCOMPtr<nsISupports> kungFuDeathGrip =
+    NS_STATIC_CAST(nsIDOMHTMLEmbedElement *, it);
+
+  nsresult rv = it->Init(mNodeInfo);
+
+  if (NS_FAILED(rv))
+    return rv;
+
+  CopyInnerTo(this, it, aDeep);
+
+  *aReturn = NS_STATIC_CAST(nsIDOMHTMLEmbedElement *, it);
+
+  NS_ADDREF(*aReturn);
+
+  return NS_OK;
+}
+
+/////////////////////////////////////////////
+// Implement nsIDOMHTMLEmbedElement interface
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Align, align)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Height, height)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Width, width)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Name, name)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Type, type)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Src, src)
+
+// nsIDOMHTMLParamElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Value, value)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, ValueType, valuetype)
+
+// nsIDOMHTMLIsIndexElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Prompt, prompt)
+
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetForm(nsIDOMHTMLFormElement** aForm)
+{
+#ifdef GATHER_ELEMENT_USEAGE_STATISTICS
+  extern void GEUS_DumpElementCounts();
+
+  GEUS_DumpElementCounts();
+#endif
+
+  *aForm = nsnull;/* XXX */
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP_(PRBool)
+nsHTMLSharedLeafElement::IsContentOfType(PRUint32 aFlags)
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::wbr)) {
+    return !(aFlags & ~(eELEMENT | eHTML | eHTML_FORM_CONTROL));
+  }
+
+  return nsGenericHTMLLeafElement::IsContentOfType(aFlags);
+}
+
+// nsIDOMHTMLBaseElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Href, href)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Target, target)
+
+// spacer element code
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::StringToAttribute(nsIAtom* aAttribute,
+                                           const nsAReadableString& aValue,
+                                           nsHTMLValue& aResult)
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if (aAttribute == nsHTMLAtoms::size) {
+      if (ParseValue(aValue, 0, aResult, eHTMLUnit_Pixel)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    } else if (aAttribute == nsHTMLAtoms::align) {
+      if (ParseAlignValue(aValue, aResult)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    } else if ((aAttribute == nsHTMLAtoms::width) ||
+               (aAttribute == nsHTMLAtoms::height)) {
+      if (ParseValueOrPercent(aValue, aResult, eHTMLUnit_Pixel)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    }
+  }
+
+  return NS_CONTENT_ATTR_NOT_THERE;
+}
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::AttributeToString(nsIAtom* aAttribute,
+                                           const nsHTMLValue& aValue,
+                                           nsAWritableString& aResult) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if (aAttribute == nsHTMLAtoms::align) {
+      if (eHTMLUnit_Enumerated == aValue.GetUnit()) {
+        AlignValueToString(aValue, aResult);
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    }
+  }
+
+  return nsGenericHTMLLeafElement::AttributeToString(aAttribute, aValue,
+                                                     aResult);
+}
+
+static void
+SpacerMapAttributesIntoRule(const nsIHTMLMappedAttributes* aAttributes,
+                            nsRuleData* aData)
+{
+  if (!aAttributes || !aData)
+    return;
+
+  nsGenericHTMLElement::MapImageMarginAttributeInto(aAttributes, aData);
+  nsGenericHTMLElement::MapImagePositionAttributeInto(aAttributes, aData);
+
+  if (aData->mPositionData) {
+    nsHTMLValue value;
+
+    const nsStyleDisplay* display = (const nsStyleDisplay*)
+      aData->mStyleContext->GetStyleData(eStyleStruct_Display);
+
+    PRBool typeIsBlock = (display->mDisplay == NS_STYLE_DISPLAY_BLOCK);
+
+    if (typeIsBlock) {
+      // width: value
+      if (aData->mPositionData->mWidth.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::width, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel) {
+          aData->mPositionData->
+            mWidth.SetFloatValue((float)value.GetPixelValue(), eCSSUnit_Pixel);
+        } else if (value.GetUnit() == eHTMLUnit_Percent) {
+          aData->mPositionData->
+            mWidth.SetPercentValue(value.GetPercentValue());
+        }
+      }
+
+      // height: value
+      if (aData->mPositionData->mHeight.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::height, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel) {
+          aData->mPositionData->
+            mHeight.SetFloatValue((float)value.GetPixelValue(),
+                                  eCSSUnit_Pixel);
+        } else if (value.GetUnit() == eHTMLUnit_Percent) {
+          aData->mPositionData->
+            mHeight.SetPercentValue(value.GetPercentValue());
+        }
+      }
+    } else {
+      // size: value
+      if (aData->mPositionData->mWidth.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::size, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel)
+          aData->mPositionData->
+            mWidth.SetFloatValue((float)value.GetPixelValue(),
+                                 eCSSUnit_Pixel);
+      }
+    }
+  } else if (aData->mDisplayData) {
+    nsHTMLValue value;
+    aAttributes->GetAttribute(nsHTMLAtoms::align, value);
+    if (value.GetUnit() == eHTMLUnit_Enumerated) {
+      PRUint8 align = (PRUint8)(value.GetIntValue());
+      if (aData->mDisplayData &&
+          aData->mDisplayData->mFloat.GetUnit() == eCSSUnit_Null) {
+        if (align == NS_STYLE_TEXT_ALIGN_LEFT)
+          aData->mDisplayData->mFloat.SetIntValue(NS_STYLE_FLOAT_LEFT,
+                                                  eCSSUnit_Enumerated);
+        else if (align == NS_STYLE_TEXT_ALIGN_RIGHT)
+          aData->mDisplayData->mFloat.SetIntValue(NS_STYLE_FLOAT_RIGHT,
+                                                  eCSSUnit_Enumerated);
+      }
+    }
+
+    if (aData->mDisplayData->mDisplay == eCSSUnit_Null) {
+      aAttributes->GetAttribute(nsHTMLAtoms::type, value);
+      if (eHTMLUnit_String == value.GetUnit()) {
+        nsAutoString tmp;
+        value.GetStringValue(tmp);
+        if (tmp.EqualsIgnoreCase("line") ||
+            tmp.EqualsIgnoreCase("vert") ||
+            tmp.EqualsIgnoreCase("vertical") ||
+            tmp.EqualsIgnoreCase("block")) {
+          // This is not strictly 100% compatible: if the spacer is given
+          // a width of zero then it is basically ignored.
+          aData->mDisplayData->mDisplay = NS_STYLE_DISPLAY_BLOCK;
+        }
+      }
+    }
+  }
+
+  nsGenericHTMLElement::MapCommonAttributesInto(aAttributes, aData);
+}
+
+static void
+PlainMapAttributesIntoRule(const nsIHTMLMappedAttributes* aAttributes,
+                           nsRuleData* aData)
+{
+  nsGenericHTMLElement::MapCommonAttributesInto(aAttributes, aData);
+}
+
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetMappedAttributeImpact(const nsIAtom* aAttribute,
+                                                  PRInt32 aModType,
+                                                  PRInt32& aHint) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if ((aAttribute == nsHTMLAtoms::usemap) ||
+        (aAttribute == nsHTMLAtoms::ismap)) {
+      aHint = NS_STYLE_HINT_FRAMECHANGE;
+    } else if (aAttribute == nsHTMLAtoms::align) {
+      aHint = NS_STYLE_HINT_REFLOW;
+    } else if (!GetCommonMappedAttributesImpact(aAttribute, aHint)) {
+      if (!GetImageMappedAttributesImpact(aAttribute, aHint)) {
+        if (!GetImageBorderAttributeImpact(aAttribute, aHint)) {
+          aHint = NS_STYLE_HINT_CONTENT;
+        }
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetAttributeMappingFunction(nsMapRuleToAttributesFunc& aMapRuleFunc) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    aMapRuleFunc = &SpacerMapAttributesIntoRule;
+  } else {
+    aMapRuleFunc = &PlainMapAttributesIntoRule;
+  }
+
+  return NS_OK;
+}
+
+
+#ifdef DEBUG
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::SizeOf(nsISizeOfHandler* aSizer,
+                                PRUint32* aResult) const
+{
+  *aResult = sizeof(*this) + BaseSizeOf(aSizer);
+
+  return NS_OK;
+}
+#endif
diff --git a/mozilla/content/html/content/src/nsHTMLSharedLeafElement.cpp b/mozilla/content/html/content/src/nsHTMLSharedLeafElement.cpp
new file mode 100644
index 00000000000..39c6252e562
--- /dev/null
+++ b/mozilla/content/html/content/src/nsHTMLSharedLeafElement.cpp
@@ -0,0 +1,433 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: NPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Communicator client code.
+ *
+ * The Initial Developer of the Original Code is 
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1998
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the NPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the NPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+#include "nsIDOMHTMLEmbedElement.h"
+#include "nsIDOMHTMLIsIndexElement.h"
+#include "nsIDOMHTMLParamElement.h"
+#include "nsIDOMHTMLBaseElement.h"
+#include "nsIDOMEventReceiver.h"
+#include "nsIHTMLContent.h"
+#include "nsGenericHTMLElement.h"
+#include "nsHTMLAtoms.h"
+#include "nsHTMLIIDs.h"
+#include "nsIStyleContext.h"
+#include "nsStyleConsts.h"
+#include "nsIPresContext.h"
+#include "nsRuleNode.h"
+#include "nsIHTMLAttributes.h"
+
+
+class nsHTMLSharedLeafElement : public nsGenericHTMLLeafElement,
+                                public nsIDOMHTMLEmbedElement,
+                                public nsIDOMHTMLIsIndexElement,
+                                public nsIDOMHTMLParamElement,
+                                public nsIDOMHTMLBaseElement
+{
+public:
+  nsHTMLSharedLeafElement();
+  virtual ~nsHTMLSharedLeafElement();
+
+  // nsISupports
+  NS_DECL_ISUPPORTS_INHERITED
+
+  // nsIDOMNode
+  NS_FORWARD_NSIDOMNODE_NO_CLONENODE(nsGenericHTMLLeafElement::)
+
+  // nsIDOMElement
+  NS_FORWARD_NSIDOMELEMENT(nsGenericHTMLLeafElement::)
+
+  // nsIDOMHTMLElement
+  NS_FORWARD_NSIDOMHTMLELEMENT(nsGenericHTMLLeafElement::)
+
+  // nsIDOMHTMLEmbedElement
+  NS_DECL_NSIDOMHTMLEMBEDELEMENT
+
+  // nsIDOMHTMLIsIndexElement
+  NS_DECL_NSIDOMHTMLISINDEXELEMENT
+
+  // nsIDOMHTMLParamElement Can't use the macro
+  // NS_DECL_NSIDOMHTMLPARAMELEMENT since some of the methods in
+  // nsIDOMHTMLParamElement clashes with methods in
+  // nsIDOMHTMLEmbedElement
+
+  NS_IMETHOD GetValue(nsAWritableString& aValue);
+  NS_IMETHOD SetValue(const nsAReadableString& aValue);
+  NS_IMETHOD GetValueType(nsAWritableString& aValueType);
+  NS_IMETHOD SetValueType(const nsAReadableString& aValueType);
+
+  // nsIDOMHTMLBaseElement
+  NS_DECL_NSIDOMHTMLBASEELEMENT
+
+  // nsIContent
+  NS_IMETHODIMP_(PRBool) IsContentOfType(PRUint32 aFlags);
+
+  NS_IMETHOD StringToAttribute(nsIAtom* aAttribute,
+                               const nsAReadableString& aValue,
+                               nsHTMLValue& aResult);
+  NS_IMETHOD AttributeToString(nsIAtom* aAttribute,
+                               const nsHTMLValue& aValue,
+                               nsAWritableString& aResult) const;
+  NS_IMETHOD GetAttributeMappingFunction(nsMapRuleToAttributesFunc& aMapRuleFunc) const;
+  NS_IMETHOD GetMappedAttributeImpact(const nsIAtom* aAttribute,
+                                      PRInt32 aModType, PRInt32& aHint) const;
+
+#ifdef DEBUG
+  NS_IMETHOD SizeOf(nsISizeOfHandler* aSizer, PRUint32* aResult) const;
+#endif
+};
+
+nsresult
+NS_NewHTMLSharedLeafElement(nsIHTMLContent** aInstancePtrResult,
+                            nsINodeInfo *aNodeInfo)
+{
+  NS_ENSURE_ARG_POINTER(aInstancePtrResult);
+
+  nsHTMLSharedLeafElement* it = new nsHTMLSharedLeafElement();
+
+  if (!it) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  nsresult rv = it->Init(aNodeInfo);
+
+  if (NS_FAILED(rv)) {
+    delete it;
+
+    return rv;
+  }
+
+  *aInstancePtrResult = NS_STATIC_CAST(nsIHTMLContent *, it);
+  NS_ADDREF(*aInstancePtrResult);
+
+  return NS_OK;
+}
+
+
+nsHTMLSharedLeafElement::nsHTMLSharedLeafElement()
+{
+}
+
+nsHTMLSharedLeafElement::~nsHTMLSharedLeafElement()
+{
+}
+
+
+NS_IMPL_ADDREF_INHERITED(nsHTMLSharedLeafElement, nsGenericElement)
+NS_IMPL_RELEASE_INHERITED(nsHTMLSharedLeafElement, nsGenericElement)
+
+
+// QueryInterface implementation for nsHTMLSharedLeafElement
+NS_HTML_CONTENT_INTERFACE_MAP_AMBIGOUS_BEGIN(nsHTMLSharedLeafElement,
+                                             nsGenericHTMLLeafElement,
+                                             nsIDOMHTMLEmbedElement)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIDOMHTMLElement, nsIDOMHTMLEmbedElement)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLEmbedElement, embed)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLParamElement, param)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLIsIndexElement, isindex)
+  NS_INTERFACE_MAP_ENTRY_IF_TAG(nsIDOMHTMLBaseElement, base)
+
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLEmbedElement, embed)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLParamElement, param)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLWBRElement, wbr)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLIsIndexElement, isindex)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLBaseElement, base)
+  NS_INTERFACE_MAP_ENTRY_CONTENT_CLASSINFO_IF_TAG(HTMLSpacerElement, spacer)
+NS_HTML_CONTENT_INTERFACE_MAP_END
+
+
+nsresult
+nsHTMLSharedLeafElement::CloneNode(PRBool aDeep, nsIDOMNode** aReturn)
+{
+  NS_ENSURE_ARG_POINTER(aReturn);
+  *aReturn = nsnull;
+
+  nsHTMLSharedLeafElement* it = new nsHTMLSharedLeafElement();
+
+  if (!it) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  nsCOMPtr<nsISupports> kungFuDeathGrip =
+    NS_STATIC_CAST(nsIDOMHTMLEmbedElement *, it);
+
+  nsresult rv = it->Init(mNodeInfo);
+
+  if (NS_FAILED(rv))
+    return rv;
+
+  CopyInnerTo(this, it, aDeep);
+
+  *aReturn = NS_STATIC_CAST(nsIDOMHTMLEmbedElement *, it);
+
+  NS_ADDREF(*aReturn);
+
+  return NS_OK;
+}
+
+/////////////////////////////////////////////
+// Implement nsIDOMHTMLEmbedElement interface
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Align, align)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Height, height)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Width, width)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Name, name)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Type, type)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Src, src)
+
+// nsIDOMHTMLParamElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Value, value)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, ValueType, valuetype)
+
+// nsIDOMHTMLIsIndexElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Prompt, prompt)
+
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetForm(nsIDOMHTMLFormElement** aForm)
+{
+#ifdef GATHER_ELEMENT_USEAGE_STATISTICS
+  extern void GEUS_DumpElementCounts();
+
+  GEUS_DumpElementCounts();
+#endif
+
+  *aForm = nsnull;/* XXX */
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP_(PRBool)
+nsHTMLSharedLeafElement::IsContentOfType(PRUint32 aFlags)
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::wbr)) {
+    return !(aFlags & ~(eELEMENT | eHTML | eHTML_FORM_CONTROL));
+  }
+
+  return nsGenericHTMLLeafElement::IsContentOfType(aFlags);
+}
+
+// nsIDOMHTMLBaseElement
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Href, href)
+NS_IMPL_STRING_ATTR(nsHTMLSharedLeafElement, Target, target)
+
+// spacer element code
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::StringToAttribute(nsIAtom* aAttribute,
+                                           const nsAReadableString& aValue,
+                                           nsHTMLValue& aResult)
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if (aAttribute == nsHTMLAtoms::size) {
+      if (ParseValue(aValue, 0, aResult, eHTMLUnit_Pixel)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    } else if (aAttribute == nsHTMLAtoms::align) {
+      if (ParseAlignValue(aValue, aResult)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    } else if ((aAttribute == nsHTMLAtoms::width) ||
+               (aAttribute == nsHTMLAtoms::height)) {
+      if (ParseValueOrPercent(aValue, aResult, eHTMLUnit_Pixel)) {
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    }
+  }
+
+  return NS_CONTENT_ATTR_NOT_THERE;
+}
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::AttributeToString(nsIAtom* aAttribute,
+                                           const nsHTMLValue& aValue,
+                                           nsAWritableString& aResult) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if (aAttribute == nsHTMLAtoms::align) {
+      if (eHTMLUnit_Enumerated == aValue.GetUnit()) {
+        AlignValueToString(aValue, aResult);
+        return NS_CONTENT_ATTR_HAS_VALUE;
+      }
+    }
+  }
+
+  return nsGenericHTMLLeafElement::AttributeToString(aAttribute, aValue,
+                                                     aResult);
+}
+
+static void
+SpacerMapAttributesIntoRule(const nsIHTMLMappedAttributes* aAttributes,
+                            nsRuleData* aData)
+{
+  if (!aAttributes || !aData)
+    return;
+
+  nsGenericHTMLElement::MapImageMarginAttributeInto(aAttributes, aData);
+  nsGenericHTMLElement::MapImagePositionAttributeInto(aAttributes, aData);
+
+  if (aData->mPositionData) {
+    nsHTMLValue value;
+
+    const nsStyleDisplay* display = (const nsStyleDisplay*)
+      aData->mStyleContext->GetStyleData(eStyleStruct_Display);
+
+    PRBool typeIsBlock = (display->mDisplay == NS_STYLE_DISPLAY_BLOCK);
+
+    if (typeIsBlock) {
+      // width: value
+      if (aData->mPositionData->mWidth.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::width, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel) {
+          aData->mPositionData->
+            mWidth.SetFloatValue((float)value.GetPixelValue(), eCSSUnit_Pixel);
+        } else if (value.GetUnit() == eHTMLUnit_Percent) {
+          aData->mPositionData->
+            mWidth.SetPercentValue(value.GetPercentValue());
+        }
+      }
+
+      // height: value
+      if (aData->mPositionData->mHeight.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::height, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel) {
+          aData->mPositionData->
+            mHeight.SetFloatValue((float)value.GetPixelValue(),
+                                  eCSSUnit_Pixel);
+        } else if (value.GetUnit() == eHTMLUnit_Percent) {
+          aData->mPositionData->
+            mHeight.SetPercentValue(value.GetPercentValue());
+        }
+      }
+    } else {
+      // size: value
+      if (aData->mPositionData->mWidth.GetUnit() == eCSSUnit_Null) {
+        aAttributes->GetAttribute(nsHTMLAtoms::size, value);
+        if (value.GetUnit() == eHTMLUnit_Pixel)
+          aData->mPositionData->
+            mWidth.SetFloatValue((float)value.GetPixelValue(),
+                                 eCSSUnit_Pixel);
+      }
+    }
+  } else if (aData->mDisplayData) {
+    nsHTMLValue value;
+    aAttributes->GetAttribute(nsHTMLAtoms::align, value);
+    if (value.GetUnit() == eHTMLUnit_Enumerated) {
+      PRUint8 align = (PRUint8)(value.GetIntValue());
+      if (aData->mDisplayData &&
+          aData->mDisplayData->mFloat.GetUnit() == eCSSUnit_Null) {
+        if (align == NS_STYLE_TEXT_ALIGN_LEFT)
+          aData->mDisplayData->mFloat.SetIntValue(NS_STYLE_FLOAT_LEFT,
+                                                  eCSSUnit_Enumerated);
+        else if (align == NS_STYLE_TEXT_ALIGN_RIGHT)
+          aData->mDisplayData->mFloat.SetIntValue(NS_STYLE_FLOAT_RIGHT,
+                                                  eCSSUnit_Enumerated);
+      }
+    }
+
+    if (aData->mDisplayData->mDisplay == eCSSUnit_Null) {
+      aAttributes->GetAttribute(nsHTMLAtoms::type, value);
+      if (eHTMLUnit_String == value.GetUnit()) {
+        nsAutoString tmp;
+        value.GetStringValue(tmp);
+        if (tmp.EqualsIgnoreCase("line") ||
+            tmp.EqualsIgnoreCase("vert") ||
+            tmp.EqualsIgnoreCase("vertical") ||
+            tmp.EqualsIgnoreCase("block")) {
+          // This is not strictly 100% compatible: if the spacer is given
+          // a width of zero then it is basically ignored.
+          aData->mDisplayData->mDisplay = NS_STYLE_DISPLAY_BLOCK;
+        }
+      }
+    }
+  }
+
+  nsGenericHTMLElement::MapCommonAttributesInto(aAttributes, aData);
+}
+
+static void
+PlainMapAttributesIntoRule(const nsIHTMLMappedAttributes* aAttributes,
+                           nsRuleData* aData)
+{
+  nsGenericHTMLElement::MapCommonAttributesInto(aAttributes, aData);
+}
+
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetMappedAttributeImpact(const nsIAtom* aAttribute,
+                                                  PRInt32 aModType,
+                                                  PRInt32& aHint) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    if ((aAttribute == nsHTMLAtoms::usemap) ||
+        (aAttribute == nsHTMLAtoms::ismap)) {
+      aHint = NS_STYLE_HINT_FRAMECHANGE;
+    } else if (aAttribute == nsHTMLAtoms::align) {
+      aHint = NS_STYLE_HINT_REFLOW;
+    } else if (!GetCommonMappedAttributesImpact(aAttribute, aHint)) {
+      if (!GetImageMappedAttributesImpact(aAttribute, aHint)) {
+        if (!GetImageBorderAttributeImpact(aAttribute, aHint)) {
+          aHint = NS_STYLE_HINT_CONTENT;
+        }
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::GetAttributeMappingFunction(nsMapRuleToAttributesFunc& aMapRuleFunc) const
+{
+  if (mNodeInfo->Equals(nsHTMLAtoms::spacer)) {
+    aMapRuleFunc = &SpacerMapAttributesIntoRule;
+  } else {
+    aMapRuleFunc = &PlainMapAttributesIntoRule;
+  }
+
+  return NS_OK;
+}
+
+
+#ifdef DEBUG
+NS_IMETHODIMP
+nsHTMLSharedLeafElement::SizeOf(nsISizeOfHandler* aSizer,
+                                PRUint32* aResult) const
+{
+  *aResult = sizeof(*this) + BaseSizeOf(aSizer);
+
+  return NS_OK;
+}
+#endif