Fix OSK flickering issue

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index bb917e53dbd4630419258f05aa4b0d9b24ba7d4f..3c7350cb620ff3fac9494520fef6ae067f78b1c8 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -246,7 +246,7 @@ class CONTENT_EXPORT RenderWidget
 
   // Handle common setup/teardown for handling IME events.
   void StartHandlingImeEvent();
-  void FinishHandlingImeEvent();
+  void FinishHandlingImeEvent(bool from_non_ime);
 
   // Returns whether we currently should handle an IME event.
   bool ShouldHandleImeEvent();
@@ -661,8 +661,12 @@ class CONTENT_EXPORT RenderWidget
   // supporting overscroll IPC notifications due to fling animation updates.
   scoped_ptr<DidOverscrollParams>* handling_event_overscroll_;
 
-  // Are we currently handling an ime event?
-  bool handling_ime_event_;
+  // The number of IME events we are handling now.
+  int handling_ime_events_count_;

[aelias_OOO_until_Jul13, 2015/10/22 03:25:07]

Please rename to "ime_guard_count_".  Strictly speaking, we are not necessarily
counting only IME events.

[Changwan Ryu, 2015/10/22 06:18:18]

Done. Also changed {Start,Finish}HandlingImeEvent names.

+  // We intentionally ignore text input update while we are handling IME events,
+  // but show_ime should be effective even if it was set in the middle of
+  // ignored state updates.
+  bool pending_show_ime_if_needed_;
 
   // Type of the input event we are currently handling.
   blink::WebInputEvent::Type handling_event_type_;
@@ -759,6 +763,12 @@ class CONTENT_EXPORT RenderWidget
   // by script etc., not by user input.
   bool text_field_is_dirty_;
 
+  // AdapterInputConnection make real changes only when it's not originating
+  // from IME. We want non-keyboard events (e.g., touch events) should be
+  // treated as NOT originating from IME, when we finish handling IME events,
+  // such as long press.
+  bool pending_update_from_non_ime_;

[aelias_OOO_until_Jul13, 2015/10/22 03:25:07]

We don't need to add this extra state.  We can just set text_field_is_dirty_,
next to where you set pending_show_ime_if_needed_ in UpdateTextInputState.  The
effect is the same.

[Changwan Ryu, 2015/10/22 06:18:18]

Hmm... They are slightly different because when text_field_is_dirty_ is set, it
will always send an update while this variable is just used in order to flip one
flag.

+
   // Stores the history of text input infos from the last ACK'ed one from the
   // current one. The size is the number of pending ACKs plus one, since we
   // intentionally keep the last ack'd value to know what the browser is