Route 'Select All' OS method through RenderWidgetHostDelegate.

content/browser/renderer_host/render_widget_host_view_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #import <objc/runtime.h>
 #include <OpenGL/gl.h>
 #include <QuartzCore/QuartzCore.h>
 
@@ skipping 3105 matching lines @@
 }
 
 - (void)selectAll:(id)sender {
   // editCommand_helper_ adds implementations for most NSResponder methods
   // dynamically. But the renderer side only sends selection results back to
   // the browser if they were triggered by a keyboard event or went through
   // one of the Select methods on RWH. Since selectAll: is called from the
   // menu handler, neither is true.
   // Explicitly call SelectAll() here to make sure the renderer returns
   // selection results.
-  WebContents* web_contents = renderWidgetHostView_->GetWebContents();
-  if (web_contents)
-    web_contents->SelectAll();
+  content::RenderWidgetHostDelegate* render_widget_host_delegate =
+      renderWidgetHostView_->render_widget_host_->delegate();
+  if (render_widget_host_delegate)
+    render_widget_host_delegate->SelectAll();
 }
 
 - (void)startSpeaking:(id)sender {
   GetRenderWidgetHostViewToUse(renderWidgetHostView_.get())->SpeakSelection();
 }
 
 - (void)stopSpeaking:(id)sender {
   GetRenderWidgetHostViewToUse(renderWidgetHostView_.get())->StopSpeaking();
 }
 
@@ skipping 163 matching lines @@
 
 // "-webkit-app-region: drag | no-drag" is implemented on Mac by excluding
 // regions that are not draggable. (See ControlRegionView in
 // native_app_window_cocoa.mm). This requires the render host view to be
 // draggable by default.
 - (BOOL)mouseDownCanMoveWindow {
   return YES;
 }
 
 @end