Add/remove spell checking markers in text inputs depending on focus.

Source/core/editing/SpellChecker.h

 /*
  * Copyright (C) 2010 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:
  * 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 65 matching lines @@
     friend class SpellCheckRequest;
 
     explicit SpellChecker(Frame*);
     ~SpellChecker();
 
     bool isAsynchronousEnabled() const;
     bool isCheckable(Range*) const;
 
     void requestCheckingFor(PassRefPtr<SpellCheckRequest>);
     void cancelCheck();
+    void cancelProcessingRequest();

[please use gerrit instead, 2013/07/30 21:32:00]

Can you reuse cancelCheck() instead? The implementation seems to be doing
exactly same task. If you think that implementation of cancelProcessingRequest()
is better, you can try modifying cancelCheck() implementation instead. We have
layout tests and unit tests in place to make sure your modifications don't break
spellchecker. You're already familiar with the layout tests:
LayoutTest/editing/spelling. You can run Blink's spellcheck unit tests like so:

  ./out/Release/webkit_unit_tests --gtest_filter="*Spell*:*spell*"

[pstanek, 2013/07/30 21:50:39]

This is something layout tests showed me as in the original patch I was using
cancelCheck(). The problem was that if some checks were added to the queue
before unfocusing an input they were also cancelled causing spellcheck-queue
test to fail. This is why I created this function to cancel only the current
request. I could reuse cancelCheck() however by adding an extra param to it.

 
     int lastRequestSequence() const
     {
         return m_lastRequestSequence;
     }
 
     int lastProcessedSequence() const
     {
         return m_lastProcessedSequence;
     }
@@ skipping 16 matching lines @@
 
     Timer<SpellChecker> m_timerToProcessQueuedRequest;
 
     RefPtr<SpellCheckRequest> m_processingRequest;
     RequestQueue m_requestQueue;
 };
 
 } // namespace WebCore
 
 #endif // SpellChecker_h