Support TSF related event handling on NativeTextField

ui/base/ime/win/tsf_event_router.h

Index: ui/base/ime/win/tsf_event_router.h
diff --git a/ui/base/ime/win/tsf_event_router.h b/ui/base/ime/win/tsf_event_router.h
index e16df27d5e15fe47788ba9c60ed941695738c385..c81bbe857325542d0419a6372512e66e338ca62d 100644
--- a/ui/base/ime/win/tsf_event_router.h
+++ b/ui/base/ime/win/tsf_event_router.h
@@ -15,6 +15,7 @@
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "ui/base/ime/text_input_type.h"
+#include "ui/base/range/range.h"
 #include "ui/base/ui_export.h"
 
 struct ITfDocumentMgr;
@@ -25,12 +26,19 @@ class TsfEventRouterObserver {
  public:
   TsfEventRouterObserver() {}
 
-  // Called when the text contents are updated.
-  virtual void OnTextUpdated() = 0;
+  // Called when the text contents are updated. If there is no composition,
+  // ui::Range::InvalidRange is passed to |composition_range|.
+  virtual void OnTextUpdated(const ui::Range& composition_range) = 0;
 
   // Called when the number of currently opened candidate windows changes.
   virtual void OnCandidateWindowCountChanged(size_t window_count) = 0;
 
+  // Called when a composition is started.

[Peter Kasting, 2012/10/27 19:00:46]

Nit: I suggest ordering these (here and everywhere else) in alphabetical order
or else in some sort of logical order, e.g. start composition/text updated/end
composition or something.

Basically anything other than "add new messages at the end, resulting in a
random order".

[Seigo Nonaka, 2012/10/27 22:20:18]

Sure, done.

+  virtual void OnTsfStartComposition() = 0;
+
+  // Called when a composition is terminated.
+  virtual void OnTsfEndComposition() = 0;
+
  protected:
   virtual ~TsfEventRouterObserver() {}
 
@@ -53,8 +61,10 @@ class UI_EXPORT TsfEventRouter {
   bool IsImeComposing();
 
   // Callbacks from the TsfEventRouterDelegate:
-  void OnTextUpdated();
+  void OnTextUpdated(const ui::Range& composition_range);
   void OnCandidateWindowCountChanged(size_t window_count);
+  void OnTsfStartComposition();
+  void OnTsfEndComposition();
 
  private:
   class TsfEventRouterDelegate;