Implement hot mode invocation for idle time spell checker

third_party/WebKit/Source/core/editing/spellcheck/IdleSpellCheckCallback.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef IdleSpellCheckCallback_h
 #define IdleSpellCheckCallback_h
 
 #include "core/dom/IdleRequestCallback.h"
 #include "core/dom/SynchronousMutationObserver.h"
+#include "core/editing/EphemeralRange.h"
+#include "core/editing/Position.h"
 #include "platform/Timer.h"
 
 namespace blink {
 
 class LocalFrame;
 class SpellCheckRequester;
 
 #define FOR_EACH_IDLE_SPELL_CHECK_CALLBACK_STATE(V) \
   V(Inactive)                                       \
   V(HotModeRequested)                               \
@@ skipping 66 matching lines @@
   void coldModeInvocation(IdleDeadline*);
   bool coldModeFinishesFullDocument() const;
 
   // Implements |SynchronousMutationObserver|.
   void contextDestroyed(Document*) final;
 
   State m_state;
   int m_idleCallbackHandle;
   mutable bool m_needsMoreColdModeInvocationForTesting;
   const Member<LocalFrame> m_frame;
-
+  uint64_t m_lastProcessedUndoStepSequence;
   TaskRunnerTimer<IdleSpellCheckCallback> m_coldModeTimer;
 };
 
 }  // namespace blink
 
 #endif  // IdleSpellCheckCallback_h