Bug 541245 part 4: Be consistent about prohibited characters such as 0xFFFE in UTF8<->UTF16 conversion code. r=smontagu

xpcom/string/public/nsUTF8Utils.h

@@ -134,10 +134,9 @@ public:
           ucs4 = UCS2_REPLACEMENT_CHAR;
         }
       else if ( ucs4 >= 0xD800 &&
-                (ucs4 <= 0xDFFF || ucs4 == 0xFFFE || ucs4 == 0xFFFF ||
-                 ucs4 >= UCS_END))
+                (ucs4 <= 0xDFFF || ucs4 >= UCS_END))
         {
-          // Surrogates and prohibited characters
+          // Surrogates and code points outside the Unicode range.
           ucs4 = UCS2_REPLACEMENT_CHAR;
         }
 

xpcom/tests/UTFStrings.h

@@ -61,6 +61,10 @@ static const UTFStringsStringPair ValidStrings[] =
       { 0xF0, 0x90, 0x80, 0x80, 0xF0, 0x90, 0x83, 0xBF } },
     { { 0xDBFF, 0xDFFF, 0xDBB7, 0xDCBA },
       { 0xF4, 0x8F, 0xBF, 0xBF, 0xF3, 0xBD, 0xB2, 0xBA } },
+    { { 0xFFFD, 0xFFFF },
+      { 0xEF, 0xBF, 0xBD, 0xEF, 0xBF, 0xBF } },
+    { { 0xFFFD, 0xFFFE, 0xFFFF },
+      { 0xEF, 0xBF, 0xBD, 0xEF, 0xBF, 0xBE, 0xEF, 0xBF, 0xBF } },
   };
 
 static const UTFStringsStringPair Invalid16Strings[] =
@@ -95,10 +99,6 @@ static const UTFStringsStringPair Invalid8Strings[] =
       { 0xC1, 0xBF } },
     { { 0xFFFD, 'x', 0x0800 },
       { 0xE0, 0x80, 0x80, 'x', 0xE0, 0xA0, 0x80 } },
-    { { 0xFFFD, 0xFFFD },
-      { 0xEF, 0xBF, 0xBD, 0xEF, 0xBF, 0xBF } },
-    { { 0xFFFD, 0xFFFD, 0xFFFD },
-      { 0xEF, 0xBF, 0xBD, 0xEF, 0xBF, 0xBE, 0xEF, 0xBF, 0xBF } },
     { { 0xFFFD, 'x', 0xFFFD },
       { 0xF0, 0x80, 0x80, 0x80, 'x', 0xF0, 0x80, 0x8F, 0x80 } },
     { { 0xFFFD, 0xFFFD },