Workaround for setComposition styling clobber

third_party/WebKit/Source/core/editing/InputMethodController.h

 /*
  * Copyright (C) 2006, 2007, 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 97 matching lines @@
 
     // Inserts the given text string in the place of the existing composition.
     // Returns true if did replace.
     bool replaceComposition(const String& text);
     // Inserts the given text string in the place of the existing composition
     // and moves caret. Returns true if did replace and moved caret successfully.
     bool replaceCompositionAndMoveCaret(const String&, int relativeCaretPosition);
 
     // Returns true if moved caret successfully.
     bool moveCaret(int newCaretPosition);
+
+    size_t computeCommonGraphemeClusterPrefixLengthForSetComposition(const String& newText) const;

[yosin_UTC9, 2016/10/04 09:00:05]

Do we really need to have
|computeCommonGraphemeClusterPrefixLengthForSetComposition()| as member
function?
It seems we can have this function as static non-member function and pass root
editable element.

[yabinh, 2016/10/11 01:42:22]

Done.

+    PlainTextRange createSelectionRangeForSetComposition(int selectionStart, int selectionEnd, size_t textLength) const;
 };
 
 } // namespace blink
 
 #endif // InputMethodController_h