Move some basic macros for working with UTF16 from intl to XPCOM; use them in

some places including the HTML parser.  Part of fix for bug 316394; the CSS
parser changes are still coming.  r=smontagu, r=mrbkap on parser changes, sr=dbaron


git-svn-id: svn://10.0.0.236/trunk@184651 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/xpcom/string/src/nsReadableUtils.cpp

@@ -1166,3 +1166,19 @@ CompareUTF8toUTF16(const nsASingleFragmentCString& aUTF8String,
 
     return 0;
   }
+
+NS_COM
+void
+AppendUCS4ToUTF16(PRUint32 aSource, nsAString& aDest)
+  {
+    NS_ASSERTION(IS_VALID_CHAR(aSource), "Invalid UCS4 char");
+    if (IS_IN_BMP(aSource))
+      {
+        aDest.Append(PRUnichar(aSource));
+      }
+    else
+      {
+        aDest.Append(H_SURROGATE(aSource));
+        aDest.Append(L_SURROGATE(aSource));
+      }
+  }