Re-limit the CJK font hack for Android to only when the content language is available

third_party/WebKit/Source/platform/fonts/android/FontCacheAndroid.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 47 matching lines @@
 AtomicString FontCache::getGenericFamilyNameForScript(
     const AtomicString& familyName,
     const FontDescription& fontDescription) {
   // If monospace, do not apply CJK hack to find i18n fonts, because
   // i18n fonts are likely not monospace. Monospace is mostly used
   // for code, but when i18n characters appear in monospace, system
   // fallback can still render the characters.
   if (familyName == FontFamilyNames::webkit_monospace)
     return familyName;
 
+  // The CJK hack below should be removed, at latest when we have
+  // serif and sans-serif versions of CJK fonts. Until then, limit it
+  // to only when the content locale is available. crbug.com/652146
+  const LayoutLocale* contentLocale = fontDescription.locale();
+  if (!contentLocale)
+    return familyName;
+
   // This is a hack to use the preferred font for CJK scripts.
   // TODO(kojii): This logic disregards either generic family name
   // or locale. We need an API that honors both to find appropriate
   // fonts. crbug.com/642340
   UChar32 examplerChar;
-  switch (fontDescription.script()) {
+  switch (contentLocale->script()) {
     case USCRIPT_SIMPLIFIED_HAN:
     case USCRIPT_TRADITIONAL_HAN:
     case USCRIPT_KATAKANA_OR_HIRAGANA:
       examplerChar = 0x4E00;  // A common character in Japanese and Chinese.
       break;
     case USCRIPT_HANGUL:
       examplerChar = 0xAC00;
       break;
     default:
       // For other scripts, use the default generic family mapping logic.
       return familyName;
   }
 
   sk_sp<SkFontMgr> fm(SkFontMgr::RefDefault());
   return getFamilyNameForCharacter(fm.get(), examplerChar, fontDescription,
                                    FontFallbackPriority::Text);
 }
 
 }  // namespace blink