OOPIF IME: Renderer Side Changes

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 8cb0010653d6e928733c5a46917e6a718de092ba..1f83e5537821c523cb56c009b751f7a191993d11 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -85,6 +85,7 @@ class CompositorDependencies;
 class ExternalPopupMenu;
 class FrameSwapMessageQueue;
 class ImeEventGuard;
+class PepperPluginInstanceImpl;
 class RenderFrameImpl;
 class RenderFrameProxy;
 class RenderWidgetCompositor;
@@ -365,6 +366,10 @@ class CONTENT_EXPORT RenderWidget
     return mouse_lock_dispatcher_.get();
   }
 
+  void set_focused_pepper_plugin(PepperPluginInstanceImpl* plugin) {
+    focused_pepper_plugin_ = plugin;
+  }
+
  protected:
   // Friend RefCounted so that the dtor can be non-public. Using this class
   // without ref-counting is an error.
@@ -769,6 +774,10 @@ class CONTENT_EXPORT RenderWidget
   // Indicates whether this widget has focus.
   bool has_focus_;
 
+  // This reference is set by the RenderFrame and is used to query the IME-
+  // related state from the plugin to later send to the browser.
+  PepperPluginInstanceImpl* focused_pepper_plugin_;

[lfg, 2016/07/07 15:13:31]

I'm not convinced this belongs in widget. This was a question that avi@ raised
in https://codereview.chromium.org/1962923002/ , and we agreed that it was
better to track plugins only in RenderFrame.

[EhsanK, 2016/07/07 20:25:07]

Technically, RW does not own this. We need this reference to
1- Forward IME IPC calls
2- Get IME related state which is collected for every compositor frame.

(1) is doable by making observer calls (though a bit ugly). For (2) we either
need this, or a reference to the render frame that owns the RW. I am not quite
sure if that is a better idea.

[lfg, 2016/07/07 20:58:26]

We could extract the local root from the WebFrameWidget, but I'm not sure if it
would be better, since all we have is a pointer to a WebWidget. I can't really
think of an easy way to handle this better (one that wouldn't involve a lot of
refactors), so unless someone else has a better suggestion, this is fine by me.

+
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };