Factor out RenderWidgetHostConnector

content/browser/renderer_host/render_widget_host_view_android.h

Index: content/browser/renderer_host/render_widget_host_view_android.h
diff --git a/content/browser/renderer_host/render_widget_host_view_android.h b/content/browser/renderer_host/render_widget_host_view_android.h
index cd3964b2c3a88cb611afff495b45073da8480865..b7d4f25fdf8b3c187397d1a9e0abcc015adc3b81 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.h
+++ b/content/browser/renderer_host/render_widget_host_view_android.h
@@ -78,6 +78,16 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
 
   void Blur();
 
+  // Interface used to observe the destruction of a RenderWidgetHostViewAndroid.
+  struct DestructionObserver {

[boliu, 2017/04/13 03:44:13]

write a proper class if you need polymorphism, no random structs

or you can juse use a base::Closure

[Jinsuk Kim, 2017/04/13 04:20:20]

Done. Turned to class.

+    virtual void RenderWidgetHostViewDestroyed(
+        RenderWidgetHostViewAndroid* rwhva) = 0;
+  };
+
+  void add_destruction_observer(DestructionObserver* connector) {
+    destruction_observers_.push_back(connector);
+  }
+
   // RenderWidgetHostView implementation.
   bool OnMessageReceived(const IPC::Message& msg) override;
   void InitAsChild(gfx::NativeView parent_view) override;
@@ -404,6 +414,8 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
   cc::mojom::MojoCompositorFrameSinkClient* renderer_compositor_frame_sink_ =
       nullptr;
 
+  std::list<DestructionObserver*> destruction_observers_;
+
   base::WeakPtrFactory<RenderWidgetHostViewAndroid> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAndroid);