Do not calculate composition bounds until IME requests.

content/renderer/render_widget.h

 // Copyright (c) 2012 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 CONTENT_RENDERER_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 331 matching lines @@
 
   // Checks if the selection bounds have been changed. If they are changed,
   // the new value will be sent to the browser process.
   void UpdateSelectionBounds();
 
   virtual void GetSelectionBounds(gfx::Rect* start, gfx::Rect* end);
 
   void OnShowHostContextMenu(ContextMenuParams* params);
 
   // Checks if the composition range or composition character bounds have been
   // changed. If they are changed, the new value will be sent to the browser

[kinaba, 2016/07/06 06:08:33]

Could you update the comment reflecting the force_update=true case?

[Seigo Nonaka, 2016/07/06 06:22:18]

Done.

   // process. This method does nothing when the browser process is not able to
   // handle composition range and composition character bounds.
-  void UpdateCompositionInfo(bool should_update_range);
+  void UpdateCompositionInfo(bool should_update_range, bool force_update);
 
   // Change the device ICC color profile while running a layout test.
   void SetDeviceColorProfileForTesting(const std::vector<char>& color_profile);
   void ResetDeviceColorProfileForTesting();
 
   // Indicates whether this widget has focus.
   bool has_focus() const { return has_focus_; }
 
   MouseLockDispatcher* mouse_lock_dispatcher() {
     return mouse_lock_dispatcher_.get();
@@ skipping 108 matching lines @@
 
 #if defined(OS_ANDROID)
   // Called when we send IME event that expects an ACK.
   void OnImeEventSentForAck(const blink::WebTextInputInfo& info);
 
   // Called by the browser process for every required IME acknowledgement.
   void OnImeEventAck();
 
   // Called by the browser process to update text input state.
   void OnRequestTextInputStateUpdate();
+
+  // Called by the browser process to update the cursor and composition
+  // information.
+  void OnRequestCursorUpdate(bool immediate_request, bool monitor_request);

[kinaba, 2016/07/06 06:08:33]

How about naming "OnRequestCompositionUpdate"?
At least for the renderer's point of view this is all about Composition, not
Cursor.

[Seigo Nonaka, 2016/07/06 06:22:18]

Make sense to me. Similarly, also I updated IPC name from Cursor to Composition
since it is actually request composition info update.

 #endif
 
   // Notify the compositor about a change in viewport size. This should be
   // used only with auto resize mode WebWidgets, as normal WebWidgets should
   // go through OnResize.
   void AutoResizeCompositor();
 
   virtual void SetDeviceScaleFactor(float device_scale_factor);
   bool SetDeviceColorProfile(const std::vector<char>& color_profile);
 
@@ skipping 224 matching lines @@
 #if defined(OS_ANDROID)
   // Indicates value in the focused text field is in dirty state, i.e. modified
   // by script etc., not by user input.
   bool text_field_is_dirty_;
 
   // 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
   // currently aware of.
   std::deque<blink::WebTextInputInfo> text_input_info_history_;
+
+  // True if the IME requests updated composition info.
+  bool monitor_composition_info_;
 #endif
 
   std::unique_ptr<RenderWidgetScreenMetricsEmulator> screen_metrics_emulator_;
 
   // Popups may be displaced when screen metrics emulation is enabled.
   // These values are used to properly adjust popup position.
   gfx::Point popup_view_origin_for_emulation_;
   gfx::Point popup_screen_origin_for_emulation_;
   float popup_origin_scale_for_emulation_;
 
@@ skipping 30 matching lines @@
 
   // Indicates whether this widget has focus.
   bool has_focus_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_