Convert SetVisuallyDeemphasized IPC to mojo

chrome/browser/ui/apps/chrome_app_delegate.h

Index: chrome/browser/ui/apps/chrome_app_delegate.h
diff --git a/chrome/browser/ui/apps/chrome_app_delegate.h b/chrome/browser/ui/apps/chrome_app_delegate.h
index 3d687f41e9672224c4c685a336089322d5647b34..4098058056d0d2594f620e12361136f741a462bd 100644
--- a/chrome/browser/ui/apps/chrome_app_delegate.h
+++ b/chrome/browser/ui/apps/chrome_app_delegate.h
@@ -13,6 +13,7 @@
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "extensions/browser/app_window/app_delegate.h"
+#include "extensions/renderer/mojo/frame_observer.mojom.h"
 #include "ui/base/window_open_disposition.h"
 #include "ui/gfx/geometry/rect.h"
 
@@ -82,6 +83,7 @@ class ChromeAppDelegate : public extensions::AppDelegate,
   std::unique_ptr<NewWindowContentsDelegate> new_window_contents_delegate_;
   base::Closure terminating_callback_;
   content::NotificationRegistrar registrar_;
+  extensions::mojom::FrameObserverPtr extensions_frame_observer_;
   base::WeakPtrFactory<ChromeAppDelegate> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeAppDelegate);