Track the active ExtensionKeybindingRegistry and make it available to EventRewriter.

chrome/browser/ui/views/toolbar/toolbar_view.h

Index: chrome/browser/ui/views/toolbar/toolbar_view.h
diff --git a/chrome/browser/ui/views/toolbar/toolbar_view.h b/chrome/browser/ui/views/toolbar/toolbar_view.h
index ddb43be86da7796b73e4529c01fd8f28c327ccd6..6b82e38b9e0d758df1fd2a5d930ead96994af42b 100644
--- a/chrome/browser/ui/views/toolbar/toolbar_view.h
+++ b/chrome/browser/ui/views/toolbar/toolbar_view.h
@@ -94,6 +94,9 @@ class ToolbarView : public views::AccessiblePaneView,
   void ExecuteExtensionCommand(const extensions::Extension* extension,
                                const extensions::Command& command);
 
+  // Returns whether the given |accelerator| is registered by an extension.
+  bool IsExtensionCommandRegistered(const ui::Accelerator& accelerator);
+
   // Shows the app (wrench) menu. |for_drop| indicates whether the menu is
   // opened for a drag-and-drop operation.
   void ShowAppMenu(bool for_drop);