diff --git a/mozilla/string/public/nsDependentString.h b/mozilla/string/public/nsDependentString.h
index ca520e7a749..ec5ba8191f7 100644
--- a/mozilla/string/public/nsDependentString.h
+++ b/mozilla/string/public/nsDependentString.h
@@ -52,20 +52,20 @@ class NS_COM nsLocalString
     
       explicit
       nsLocalString( const PRUnichar* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalString( const PRUnichar* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), NS_CONST_CAST(PRUnichar*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral));
             }
         }
 
@@ -91,20 +91,20 @@ class NS_COM nsLocalCString
     
       explicit
       nsLocalCString( const char* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalCString( const char* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), NS_CONST_CAST(char*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral));
             }
         }
 
diff --git a/mozilla/string/public/nsLocalString.h b/mozilla/string/public/nsLocalString.h
index ca520e7a749..ec5ba8191f7 100644
--- a/mozilla/string/public/nsLocalString.h
+++ b/mozilla/string/public/nsLocalString.h
@@ -52,20 +52,20 @@ class NS_COM nsLocalString
     
       explicit
       nsLocalString( const PRUnichar* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalString( const PRUnichar* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), NS_CONST_CAST(PRUnichar*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral));
             }
         }
 
@@ -91,20 +91,20 @@ class NS_COM nsLocalCString
     
       explicit
       nsLocalCString( const char* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalCString( const char* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), NS_CONST_CAST(char*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral));
             }
         }
 
diff --git a/mozilla/string/public/nsSlidingString.h b/mozilla/string/public/nsSlidingString.h
index 4c0d24f1797..181e59dd64c 100755
--- a/mozilla/string/public/nsSlidingString.h
+++ b/mozilla/string/public/nsSlidingString.h
@@ -25,8 +25,13 @@
 #ifndef nsSlidingString_h___
 #define nsSlidingString_h___
 
-#include "nsAReadableString.h"
+#ifndef nsAString_h___
+#include "nsAString.h"
+#endif
+
+#ifndef nsSharedBufferList_h___
 #include "nsSharedBufferList.h"
+#endif
 
 
   /**
@@ -90,14 +95,14 @@ class NS_COM nsSlidingSubstring
       nsSlidingSubstring( const nsSlidingSubstring& aString, const nsReadingIterator<PRUnichar>& aStart, const nsReadingIterator<PRUnichar>& aEnd );
       nsSlidingSubstring( const nsSlidingString& );
       nsSlidingSubstring( const nsSlidingString& aString, const nsReadingIterator<PRUnichar>& aStart, const nsReadingIterator<PRUnichar>& aEnd );
-      explicit nsSlidingSubstring( const nsAReadableString& );
+      explicit nsSlidingSubstring( const nsAString& );
         // copy the supplied string into a new buffer ... there will be no modifying instance over this buffer list
 
       void Rebind( const nsSlidingSubstring& );
       void Rebind( const nsSlidingSubstring&, const nsReadingIterator<PRUnichar>&, const nsReadingIterator<PRUnichar>& );
       void Rebind( const nsSlidingString& );
       void Rebind( const nsSlidingString&, const nsReadingIterator<PRUnichar>&, const nsReadingIterator<PRUnichar>& );
-      void Rebind( const nsAReadableString& );
+      void Rebind( const nsAString& );
 
      ~nsSlidingSubstring();
 
@@ -106,6 +111,7 @@ class NS_COM nsSlidingSubstring
     protected:
       nsSlidingSubstring( nsSlidingSharedBufferList* aBufferList );
       virtual const PRUnichar* GetReadableFragment( nsReadableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) const;
+      virtual       PRUnichar* GetWritableFragment( nsWritableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) { }
 
     private:
         // can't assign into me, I'm a read-only reference
@@ -176,8 +182,9 @@ class NS_COM nsSlidingString
 
     protected:
       virtual const PRUnichar* GetReadableFragment( nsReadableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) const;
+      virtual       PRUnichar* GetWritableFragment( nsWritableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) { }
 
-      void InsertReadable( const nsAReadableString&, const nsReadingIterator<PRUnichar>& ); // ...to implement |nsScannerString::UngetReadable| 
+      void InsertReadable( const nsAString&, const nsReadingIterator<PRUnichar>& ); // ...to implement |nsScannerString::UngetReadable| 
 
     private:
 
diff --git a/mozilla/string/src/nsSlidingString.cpp b/mozilla/string/src/nsSlidingString.cpp
index f574779c281..51a5842581d 100755
--- a/mozilla/string/src/nsSlidingString.cpp
+++ b/mozilla/string/src/nsSlidingString.cpp
@@ -99,7 +99,7 @@ nsSlidingSubstring::nsSlidingSubstring( nsSlidingSharedBufferList* aBufferList )
 typedef const nsSharedBufferList::Buffer* Buffer_ptr;
 
 static nsSharedBufferList::Buffer*
-AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAReadableString& aDataSource )
+AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAString& aDataSource )
   {
     typedef const PRUnichar* PRUnichar_ptr;
 
@@ -131,7 +131,7 @@ AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAReadableS
     return result;
   }
 
-nsSlidingSubstring::nsSlidingSubstring( const nsAReadableString& aSourceString )
+nsSlidingSubstring::nsSlidingSubstring( const nsAString& aSourceString )
     : mBufferList(new nsSlidingSharedBufferList(AllocateContiguousHandleWithData(Buffer_ptr(0), aSourceString)))
   {
     init_range_from_buffer_list();
@@ -189,7 +189,7 @@ nsSlidingSubstring::Rebind( const nsSlidingString& aString, const nsReadingItera
   }
 
 void
-nsSlidingSubstring::Rebind( const nsAReadableString& aSourceString )
+nsSlidingSubstring::Rebind( const nsAString& aSourceString )
   {
     release_ownership_of_buffer_list();
     mBufferList = new nsSlidingSharedBufferList(AllocateContiguousHandleWithData(Buffer_ptr(0), aSourceString));
@@ -291,7 +291,7 @@ nsSlidingString::AppendBuffer( PRUnichar* aStorageStart, PRUnichar* aDataEnd, PR
   }
 
 void
-nsSlidingString::InsertReadable( const nsAReadableString& aReadable, const nsReadingIterator<PRUnichar>& aInsertPoint )
+nsSlidingString::InsertReadable( const nsAString& aReadable, const nsReadingIterator<PRUnichar>& aInsertPoint )
     /*
      * Warning: this routine manipulates the shared buffer list in an unexpected way.
      *  The original design did not really allow for insertions, but this call promises
diff --git a/mozilla/xpcom/string/public/nsDependentString.h b/mozilla/xpcom/string/public/nsDependentString.h
index ca520e7a749..ec5ba8191f7 100644
--- a/mozilla/xpcom/string/public/nsDependentString.h
+++ b/mozilla/xpcom/string/public/nsDependentString.h
@@ -52,20 +52,20 @@ class NS_COM nsLocalString
     
       explicit
       nsLocalString( const PRUnichar* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalString( const PRUnichar* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), NS_CONST_CAST(PRUnichar*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral));
             }
         }
 
@@ -91,20 +91,20 @@ class NS_COM nsLocalCString
     
       explicit
       nsLocalCString( const char* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalCString( const char* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), NS_CONST_CAST(char*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral));
             }
         }
 
diff --git a/mozilla/xpcom/string/public/nsLocalString.h b/mozilla/xpcom/string/public/nsLocalString.h
index ca520e7a749..ec5ba8191f7 100644
--- a/mozilla/xpcom/string/public/nsLocalString.h
+++ b/mozilla/xpcom/string/public/nsLocalString.h
@@ -52,20 +52,20 @@ class NS_COM nsLocalString
     
       explicit
       nsLocalString( const PRUnichar* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalString( const PRUnichar* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(PRUnichar*, aLiteral), NS_CONST_CAST(PRUnichar*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<PRUnichar>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(PRUnichar*, aLiteral)+nsCharTraits<PRUnichar>::length(aLiteral)) : NS_CONST_CAST(PRUnichar*, aLiteral));
             }
         }
 
@@ -91,20 +91,20 @@ class NS_COM nsLocalCString
     
       explicit
       nsLocalCString( const char* aLiteral )
-          : mHandle(aLiteral, aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral))
         {
           // nothing else to do here
         }
 
       nsLocalCString( const char* aLiteral, PRUint32 aLength )
-          : mHandle(aLiteral, aLiteral+aLength)
+          : mHandle(NS_CONST_CAST(char*, aLiteral), NS_CONST_CAST(char*, aLiteral)+aLength)
         {
             // This is an annoying hack.  Callers should be fixed to use the other
             //  constructor if they don't really know the length.
           if ( aLength == PRUint32(-1) )
             {
 //            NS_WARNING("Tell scc: Caller constructing a string doesn't know the real length.  Please use the other constructor.");
-              mHandle.DataEnd(aLiteral ? (aLiteral+nsCharTraits<char>::length(aLiteral)) : aLiteral);
+              mHandle.DataEnd(aLiteral ? (NS_CONST_CAST(char*, aLiteral)+nsCharTraits<char>::length(aLiteral)) : NS_CONST_CAST(char*, aLiteral));
             }
         }
 
diff --git a/mozilla/xpcom/string/public/nsSlidingString.h b/mozilla/xpcom/string/public/nsSlidingString.h
index 4c0d24f1797..181e59dd64c 100755
--- a/mozilla/xpcom/string/public/nsSlidingString.h
+++ b/mozilla/xpcom/string/public/nsSlidingString.h
@@ -25,8 +25,13 @@
 #ifndef nsSlidingString_h___
 #define nsSlidingString_h___
 
-#include "nsAReadableString.h"
+#ifndef nsAString_h___
+#include "nsAString.h"
+#endif
+
+#ifndef nsSharedBufferList_h___
 #include "nsSharedBufferList.h"
+#endif
 
 
   /**
@@ -90,14 +95,14 @@ class NS_COM nsSlidingSubstring
       nsSlidingSubstring( const nsSlidingSubstring& aString, const nsReadingIterator<PRUnichar>& aStart, const nsReadingIterator<PRUnichar>& aEnd );
       nsSlidingSubstring( const nsSlidingString& );
       nsSlidingSubstring( const nsSlidingString& aString, const nsReadingIterator<PRUnichar>& aStart, const nsReadingIterator<PRUnichar>& aEnd );
-      explicit nsSlidingSubstring( const nsAReadableString& );
+      explicit nsSlidingSubstring( const nsAString& );
         // copy the supplied string into a new buffer ... there will be no modifying instance over this buffer list
 
       void Rebind( const nsSlidingSubstring& );
       void Rebind( const nsSlidingSubstring&, const nsReadingIterator<PRUnichar>&, const nsReadingIterator<PRUnichar>& );
       void Rebind( const nsSlidingString& );
       void Rebind( const nsSlidingString&, const nsReadingIterator<PRUnichar>&, const nsReadingIterator<PRUnichar>& );
-      void Rebind( const nsAReadableString& );
+      void Rebind( const nsAString& );
 
      ~nsSlidingSubstring();
 
@@ -106,6 +111,7 @@ class NS_COM nsSlidingSubstring
     protected:
       nsSlidingSubstring( nsSlidingSharedBufferList* aBufferList );
       virtual const PRUnichar* GetReadableFragment( nsReadableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) const;
+      virtual       PRUnichar* GetWritableFragment( nsWritableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) { }
 
     private:
         // can't assign into me, I'm a read-only reference
@@ -176,8 +182,9 @@ class NS_COM nsSlidingString
 
     protected:
       virtual const PRUnichar* GetReadableFragment( nsReadableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) const;
+      virtual       PRUnichar* GetWritableFragment( nsWritableFragment<PRUnichar>&, nsFragmentRequest, PRUint32 ) { }
 
-      void InsertReadable( const nsAReadableString&, const nsReadingIterator<PRUnichar>& ); // ...to implement |nsScannerString::UngetReadable| 
+      void InsertReadable( const nsAString&, const nsReadingIterator<PRUnichar>& ); // ...to implement |nsScannerString::UngetReadable| 
 
     private:
 
diff --git a/mozilla/xpcom/string/src/nsSlidingString.cpp b/mozilla/xpcom/string/src/nsSlidingString.cpp
index f574779c281..51a5842581d 100755
--- a/mozilla/xpcom/string/src/nsSlidingString.cpp
+++ b/mozilla/xpcom/string/src/nsSlidingString.cpp
@@ -99,7 +99,7 @@ nsSlidingSubstring::nsSlidingSubstring( nsSlidingSharedBufferList* aBufferList )
 typedef const nsSharedBufferList::Buffer* Buffer_ptr;
 
 static nsSharedBufferList::Buffer*
-AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAReadableString& aDataSource )
+AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAString& aDataSource )
   {
     typedef const PRUnichar* PRUnichar_ptr;
 
@@ -131,7 +131,7 @@ AllocateContiguousHandleWithData( Buffer_ptr aDummyHandlePtr, const nsAReadableS
     return result;
   }
 
-nsSlidingSubstring::nsSlidingSubstring( const nsAReadableString& aSourceString )
+nsSlidingSubstring::nsSlidingSubstring( const nsAString& aSourceString )
     : mBufferList(new nsSlidingSharedBufferList(AllocateContiguousHandleWithData(Buffer_ptr(0), aSourceString)))
   {
     init_range_from_buffer_list();
@@ -189,7 +189,7 @@ nsSlidingSubstring::Rebind( const nsSlidingString& aString, const nsReadingItera
   }
 
 void
-nsSlidingSubstring::Rebind( const nsAReadableString& aSourceString )
+nsSlidingSubstring::Rebind( const nsAString& aSourceString )
   {
     release_ownership_of_buffer_list();
     mBufferList = new nsSlidingSharedBufferList(AllocateContiguousHandleWithData(Buffer_ptr(0), aSourceString));
@@ -291,7 +291,7 @@ nsSlidingString::AppendBuffer( PRUnichar* aStorageStart, PRUnichar* aDataEnd, PR
   }
 
 void
-nsSlidingString::InsertReadable( const nsAReadableString& aReadable, const nsReadingIterator<PRUnichar>& aInsertPoint )
+nsSlidingString::InsertReadable( const nsAString& aReadable, const nsReadingIterator<PRUnichar>& aInsertPoint )
     /*
      * Warning: this routine manipulates the shared buffer list in an unexpected way.
      *  The original design did not really allow for insertions, but this call promises