The first step for enabling off-the-spot IME on Pepper on ChromeOS/Linux.

content/renderer/render_view.h

Index: content/renderer/render_view.h
diff --git a/content/renderer/render_view.h b/content/renderer/render_view.h
index ac79586615d1eb80b608dc9532984fce6326c315..a4e96c0ffc8e7e8161d6bee5eaf40a096dd93f97 100644
--- a/content/renderer/render_view.h
+++ b/content/renderer/render_view.h
@@ -305,6 +305,9 @@ class RenderView : public RenderWidget,
   WebKit::WebPlugin* CreatePluginNoCheck(WebKit::WebFrame* frame,
                                          const WebKit::WebPluginParams& params);
 
+  // Informs the render view that the given plugin has gained or lost focus.
+  void PpapiPluginFocusChanged(bool focused);
+
 #if defined(OS_MACOSX)
   // Informs the render view that the given plugin has gained or lost focus.
   void PluginFocusChanged(bool focused, int plugin_id);
@@ -609,6 +612,14 @@ class RenderView : public RenderWidget,
   virtual void OnWasHidden();
   virtual void OnWasRestored(bool needs_repainting);
   virtual bool SupportsAsynchronousSwapBuffers() OVERRIDE;
+  virtual void OnImeSetComposition(
+      const string16& text,
+      const std::vector<WebKit::WebCompositionUnderline>& underlines,
+      int selection_start,
+      int selection_end) OVERRIDE;
+  virtual void OnImeConfirmComposition(const string16& text) OVERRIDE;
+  virtual void GetTextInputType(WebKit::WebTextInputType* type,
+                                WebKit::WebRect* caret_bounds) OVERRIDE;
 
  private:
   // For unit tests.
@@ -1050,6 +1061,9 @@ class RenderView : public RenderWidget,
   // or tab focus and visibily. These are non-owning references.
   std::set<WebPluginDelegateProxy*> plugin_delegates_;
 
+  // Whether or not the focus is on a PPAPI plugin
+  bool is_ppapi_plugin_focused_;

[brettw, 2011/05/26 02:57:26]

Can this state be tracked on the PepperPluginDelegateImpl? RenderView can call
into that to query state as needed. But it's nice to keep RenderView as small as
possible and keep the Pepper stuff in one spot.

[kinaba, 2011/05/30 03:07:11]

Done.
(The variable is moved to PepperPluginDelegateImpl, but I still kept
the notification function PpapiPluginFocusChanged for invoking
UpdateInputMethod() at that timing.)

+
   // Helper objects ------------------------------------------------------------
 
   ScopedRunnableMethodFactory<RenderView> accessibility_method_factory_;