diff --git a/mozilla/content/base/src/nsDocumentViewer.cpp b/mozilla/content/base/src/nsDocumentViewer.cpp
index d9173c5d5f0..088a22c32b2 100644
--- a/mozilla/content/base/src/nsDocumentViewer.cpp
+++ b/mozilla/content/base/src/nsDocumentViewer.cpp
@@ -689,9 +689,9 @@ DocumentViewerImpl::InitPresentationStuff(PRBool aDoInitialReflow)
         // inside the frameset...
 
         sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                           NS_STYLE_OVERFLOW_HIDDEN);
+                                           nsIScrollable::Scrollbar_Never);
         sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                           NS_STYLE_OVERFLOW_HIDDEN);
+                                           nsIScrollable::Scrollbar_Never);
       } else {
         sc->ResetScrollbarPreferences();
       }
diff --git a/mozilla/content/html/document/src/nsHTMLContentSink.cpp b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
index 0b99103f65b..650b90da514 100644
--- a/mozilla/content/html/document/src/nsHTMLContentSink.cpp
+++ b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
@@ -3654,10 +3654,10 @@ HTMLContentSink::StartLayout()
     if (mFrameset) {
       scrollableContainer->
         SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                       NS_STYLE_OVERFLOW_HIDDEN);
+                                       nsIScrollable::Scrollbar_Never);
       scrollableContainer->
         SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                       NS_STYLE_OVERFLOW_HIDDEN);
+                                       nsIScrollable::Scrollbar_Never);
     } else {
       scrollableContainer->ResetScrollbarPreferences();
     }
diff --git a/mozilla/docshell/base/nsDocShell.cpp b/mozilla/docshell/base/nsDocShell.cpp
index 137e76dcabe..e412428bd2a 100644
--- a/mozilla/docshell/base/nsDocShell.cpp
+++ b/mozilla/docshell/base/nsDocShell.cpp
@@ -268,8 +268,8 @@ nsDocShell::nsDocShell():
     mMarginHeight(0),
     mItemType(typeContent),
     mContentListener(nsnull),
-    mCurrentScrollbarPref(-1, -1),
-    mDefaultScrollbarPref(-1, -1),
+    mCurrentScrollbarPref(Scrollbar_Auto, Scrollbar_Auto),
+    mDefaultScrollbarPref(Scrollbar_Auto, Scrollbar_Auto),
     mEditorData(nsnull),
     mParent(nsnull),
     mTreeOwner(nsnull),
diff --git a/mozilla/dom/src/base/nsBarProps.cpp b/mozilla/dom/src/base/nsBarProps.cpp
index 6eb053d02c0..4bb25ae7406 100644
--- a/mozilla/dom/src/base/nsBarProps.cpp
+++ b/mozilla/dom/src/base/nsBarProps.cpp
@@ -275,15 +275,14 @@ ScrollbarsPropImpl::GetVisible(PRBool *aVisible)
       do_QueryInterface(mDOMWindow->GetDocShell());
 
     if (scroller) {
-      PRInt32 prefValue = aVisible ? NS_STYLE_OVERFLOW_AUTO :
-                                     NS_STYLE_OVERFLOW_HIDDEN;
+      PRInt32 prefValue;
       scroller->GetDefaultScrollbarPreferences(
                   nsIScrollable::ScrollOrientation_Y, &prefValue);
-      if (prefValue == NS_STYLE_OVERFLOW_HIDDEN) // try the other way
+      if (prefValue == nsIScrollable::Scrollbar_Never) // try the other way
         scroller->GetDefaultScrollbarPreferences(
                     nsIScrollable::ScrollOrientation_X, &prefValue);
 
-      if (prefValue == NS_STYLE_OVERFLOW_HIDDEN)
+      if (prefValue == nsIScrollable::Scrollbar_Never)
         *aVisible = PR_FALSE;
     }
   }
@@ -307,8 +306,8 @@ ScrollbarsPropImpl::SetVisible(PRBool aVisible)
       do_QueryInterface(mDOMWindow->GetDocShell());
 
     if (scroller) {
-      PRInt32 prefValue = aVisible ? NS_STYLE_OVERFLOW_AUTO :
-                                     NS_STYLE_OVERFLOW_HIDDEN;
+      PRInt32 prefValue = aVisible ? nsIScrollable::Scrollbar_Auto :
+                                     nsIScrollable::Scrollbar_Never ;
       scroller->SetDefaultScrollbarPreferences(
                   nsIScrollable::ScrollOrientation_Y, prefValue);
       scroller->SetDefaultScrollbarPreferences(
diff --git a/mozilla/layout/base/nsCSSFrameConstructor.cpp b/mozilla/layout/base/nsCSSFrameConstructor.cpp
index 0f246117543..5fad6370a4f 100644
--- a/mozilla/layout/base/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/base/nsCSSFrameConstructor.cpp
@@ -3854,7 +3854,7 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
           PRInt32 scrolling = -1;
           // XXX We should get prefs for X and Y and deal with these independently!
           scrollableContainer->GetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,&scrolling);
-          if (NS_STYLE_OVERFLOW_HIDDEN == scrolling) {
+          if (nsIScrollable::Scrollbar_Never == scrolling) {
             isScrollable = PR_FALSE;
           }
           // XXX NS_STYLE_OVERFLOW_SCROLL should create 'always on' scrollbars
diff --git a/mozilla/layout/base/nsDocumentViewer.cpp b/mozilla/layout/base/nsDocumentViewer.cpp
index d9173c5d5f0..088a22c32b2 100644
--- a/mozilla/layout/base/nsDocumentViewer.cpp
+++ b/mozilla/layout/base/nsDocumentViewer.cpp
@@ -689,9 +689,9 @@ DocumentViewerImpl::InitPresentationStuff(PRBool aDoInitialReflow)
         // inside the frameset...
 
         sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,
-                                           NS_STYLE_OVERFLOW_HIDDEN);
+                                           nsIScrollable::Scrollbar_Never);
         sc->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X,
-                                           NS_STYLE_OVERFLOW_HIDDEN);
+                                           nsIScrollable::Scrollbar_Never);
       } else {
         sc->ResetScrollbarPreferences();
       }
diff --git a/mozilla/layout/generic/nsFrameFrame.cpp b/mozilla/layout/generic/nsFrameFrame.cpp
index 63f215c82b8..e363f669351 100644
--- a/mozilla/layout/generic/nsFrameFrame.cpp
+++ b/mozilla/layout/generic/nsFrameFrame.cpp
@@ -648,23 +648,24 @@ nsSubDocumentFrame::ShowDocShell()
     PRInt32 scrolling = GetStyleDisplay()->mOverflow;
     PRInt32 scrollX, scrollY;
     switch (scrolling) {
+      case NS_STYLE_OVERFLOW_VISIBLE:
+      case NS_STYLE_OVERFLOW_AUTO:
+        scrollX = scrollY = nsIScrollable::Scrollbar_Auto;
+        break;
+      case NS_STYLE_OVERFLOW_HIDDEN:
       case NS_STYLE_OVERFLOW_CLIP:
-        scrollX = NS_STYLE_OVERFLOW_HIDDEN;
-        scrollY = NS_STYLE_OVERFLOW_HIDDEN;
+        scrollX = scrollY = nsIScrollable::Scrollbar_Never;
+        break;
+      case NS_STYLE_OVERFLOW_SCROLL:
+        scrollX = scrollY = nsIScrollable::Scrollbar_Always;
         break;
       case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
-        scrollX = NS_STYLE_OVERFLOW_SCROLL;
-        scrollY = NS_STYLE_OVERFLOW_HIDDEN;
+        scrollX = nsIScrollable::Scrollbar_Always;
+        scrollY = nsIScrollable::Scrollbar_Never;
         break;
       case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
-        scrollX = NS_STYLE_OVERFLOW_HIDDEN;
-        scrollY = NS_STYLE_OVERFLOW_SCROLL;
-        break;
-      case NS_STYLE_OVERFLOW_VISIBLE:
-        scrollX = scrollY = NS_STYLE_OVERFLOW_AUTO;
-        break;
-      default:
-        scrollX = scrollY = scrolling;
+        scrollX = nsIScrollable::Scrollbar_Never;
+        scrollY = nsIScrollable::Scrollbar_Always;
         break;
     }
 
diff --git a/mozilla/layout/html/document/src/nsFrameFrame.cpp b/mozilla/layout/html/document/src/nsFrameFrame.cpp
index 63f215c82b8..e363f669351 100644
--- a/mozilla/layout/html/document/src/nsFrameFrame.cpp
+++ b/mozilla/layout/html/document/src/nsFrameFrame.cpp
@@ -648,23 +648,24 @@ nsSubDocumentFrame::ShowDocShell()
     PRInt32 scrolling = GetStyleDisplay()->mOverflow;
     PRInt32 scrollX, scrollY;
     switch (scrolling) {
+      case NS_STYLE_OVERFLOW_VISIBLE:
+      case NS_STYLE_OVERFLOW_AUTO:
+        scrollX = scrollY = nsIScrollable::Scrollbar_Auto;
+        break;
+      case NS_STYLE_OVERFLOW_HIDDEN:
       case NS_STYLE_OVERFLOW_CLIP:
-        scrollX = NS_STYLE_OVERFLOW_HIDDEN;
-        scrollY = NS_STYLE_OVERFLOW_HIDDEN;
+        scrollX = scrollY = nsIScrollable::Scrollbar_Never;
+        break;
+      case NS_STYLE_OVERFLOW_SCROLL:
+        scrollX = scrollY = nsIScrollable::Scrollbar_Always;
         break;
       case NS_STYLE_OVERFLOW_SCROLLBARS_HORIZONTAL:
-        scrollX = NS_STYLE_OVERFLOW_SCROLL;
-        scrollY = NS_STYLE_OVERFLOW_HIDDEN;
+        scrollX = nsIScrollable::Scrollbar_Always;
+        scrollY = nsIScrollable::Scrollbar_Never;
         break;
       case NS_STYLE_OVERFLOW_SCROLLBARS_VERTICAL:
-        scrollX = NS_STYLE_OVERFLOW_HIDDEN;
-        scrollY = NS_STYLE_OVERFLOW_SCROLL;
-        break;
-      case NS_STYLE_OVERFLOW_VISIBLE:
-        scrollX = scrollY = NS_STYLE_OVERFLOW_AUTO;
-        break;
-      default:
-        scrollX = scrollY = scrolling;
+        scrollX = nsIScrollable::Scrollbar_Never;
+        scrollY = nsIScrollable::Scrollbar_Always;
         break;
     }
 
diff --git a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
index 0f246117543..5fad6370a4f 100644
--- a/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
+++ b/mozilla/layout/html/style/src/nsCSSFrameConstructor.cpp
@@ -3854,7 +3854,7 @@ nsCSSFrameConstructor::ConstructRootFrame(nsIPresShell*        aPresShell,
           PRInt32 scrolling = -1;
           // XXX We should get prefs for X and Y and deal with these independently!
           scrollableContainer->GetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,&scrolling);
-          if (NS_STYLE_OVERFLOW_HIDDEN == scrolling) {
+          if (nsIScrollable::Scrollbar_Never == scrolling) {
             isScrollable = PR_FALSE;
           }
           // XXX NS_STYLE_OVERFLOW_SCROLL should create 'always on' scrollbars