Fix scriptCodeForHanFromSubtags() may return non-Han scripts

third_party/WebKit/Source/platform/text/LocaleToScriptMapping.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 494 matching lines @@
         size_t len = (end == kNotFound ? locale.length() : end) - begin;
         UScriptCode script;
         switch (len) {
         case 2: // region = 2ALPHA / 3DIGIT
             script = scriptCodeForHanFromRegion(locale.substring(begin, len));
             if (script != USCRIPT_COMMON)
                 return script;
             break;
         case 4: // script = 4ALPHA
             script = scriptNameToCode(locale.substring(begin, len));
-            if (script != USCRIPT_INVALID_CODE)
+            if (isUnambiguousHanScript(script))
                 return script;
         }
     }
 
     return USCRIPT_COMMON;
 }
 
 } // namespace blink