linux_aura: Port GtkKeybindingsHandler to Aura.

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index fa5915613eb43e9c2e7a556542e1dd3bbad7c9f7..002cc22ddabb0d2ddb128764a89cf67a9a0cdec1 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -525,6 +525,11 @@ class CONTENT_EXPORT RenderWidgetHostViewAura
   // Detaches |this| from the input method object.
   void DetachFromInputMethod();
 
+  // Before calling RenderWidgetHost::ForwardKeyboardEvent(), this method
+  // calls our keybindings handler against the event and send matched
+  // edit commands to renderer instead.
+  void ForwardKeyboardEvent(const NativeWebKeyboardEvent& event);
+
   // Dismisses a Web Popup on a mouse or touch press outside the popup and its
   // parent.
   void ApplyEventFilterForPopupExit(ui::LocatedEvent* event);