Convert SetVisuallyDeemphasized IPC to mojo

extensions/renderer/extensions_render_frame_observer.h

Index: extensions/renderer/extensions_render_frame_observer.h
diff --git a/extensions/renderer/extensions_render_frame_observer.h b/extensions/renderer/extensions_render_frame_observer.h
index 35f03a9085ea21d810316e1be15748a07e0f1b7d..e7f50faf14a803eb66cf2d22e285287475a9f244 100644
--- a/extensions/renderer/extensions_render_frame_observer.h
+++ b/extensions/renderer/extensions_render_frame_observer.h
@@ -9,19 +9,30 @@
 
 #include "base/macros.h"
 #include "content/public/renderer/render_frame_observer.h"
+#include "extensions/features/features.h"
+#include "extensions/renderer/mojo/frame_observer.mojom.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
 
 namespace extensions {
 
 // This class holds the extensions specific parts of RenderFrame, and has the
 // same lifetime.
-class ExtensionsRenderFrameObserver
-    : public content::RenderFrameObserver {
+class ExtensionsRenderFrameObserver : public content::RenderFrameObserver,
+                                      public mojom::FrameObserver {
  public:
+  void Create(mojom::FrameObserverRequest request);

[Devlin, 2017/03/04 02:19:41]

"Create()" is a little strange here, since usually Foo::Create() would be a
method to create a new Foo.  Maybe AssociateBinding()?  Also, it looks like
maybe this method can be private?

[catmullings, 2017/03/06 21:20:40]

Done.

+
   explicit ExtensionsRenderFrameObserver(
       content::RenderFrame* render_frame);
   ~ExtensionsRenderFrameObserver() override;
 
  private:
+#if BUILDFLAG(ENABLE_EXTENSIONS)

[Devlin, 2017/03/04 02:19:41]

Since we're moving this to an extensions/ file, we can know that extensions are
enabled.

[catmullings, 2017/03/06 21:20:40]

Done.

+  // Toggles visual muting of the render view area. This is on when a
+  // constrained window is showing.
+  void SetVisuallyDeemphasized(bool deemphasized) override;
+#endif
+
   // RenderFrameObserver implementation.
   void DetailedConsoleMessageAdded(const base::string16& message,
                                    const base::string16& source,
@@ -30,6 +41,11 @@ class ExtensionsRenderFrameObserver
                                    int32_t severity_level) override;
   void OnDestruct() override;
 
+  // true if webview is overlayed with grey color.
+  bool webview_visually_deemphasized_;
+
+  mojo::BindingSet<mojom::FrameObserver> bindings_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionsRenderFrameObserver);
 };