Abstract base 'ExtensionView' to Fix DEPS violation in extension_view_host.h

chrome/browser/ui/views/extensions/extension_dialog.h

Index: chrome/browser/ui/views/extensions/extension_dialog.h
diff --git a/chrome/browser/ui/views/extensions/extension_dialog.h b/chrome/browser/ui/views/extensions/extension_dialog.h
index f7570de7e610a1daa834c0d15db993e19006e4fe..7e4df18f1a56416ba5c899185ca389f0373ac06d 100644
--- a/chrome/browser/ui/views/extensions/extension_dialog.h
+++ b/chrome/browser/ui/views/extensions/extension_dialog.h
@@ -14,6 +14,7 @@
 #include "ui/views/window/dialog_delegate.h"
 
 class ExtensionDialogObserver;
+class ExtensionViewViews;
 class GURL;
 class Profile;
 
@@ -92,6 +93,7 @@ class ExtensionDialog : public views::DialogDelegate,
                   ExtensionDialogObserver* observer);
 
   void InitWindow(aura::Window* parent_window, int width, int height);
+  ExtensionViewViews* GetExtensionView() const;
 
   // Window Title
   base::string16 window_title_;