app_shell: Fix focus on opening new app windows

extensions/shell/browser/shell_app_delegate.h

 // Copyright 2014 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.
 
 #ifndef EXTENSIONS_SHELL_BROWSER_SHELL_APP_DELEGATE_H_
 #define EXTENSIONS_SHELL_BROWSER_SHELL_APP_DELEGATE_H_
 
 #include "extensions/browser/app_window/app_delegate.h"
+#include "content/public/browser/web_contents_observer.h"
 
 namespace extensions {
 
-// app_shell's AppDelegate implementation.
-class ShellAppDelegate : public AppDelegate {
+// AppDelegate implementation for app_shell. Sets focus after the WebContents is
+// created. Ignores most operations that would create a new dialog or window.
+class ShellAppDelegate : public AppDelegate,
+                         public content::WebContentsObserver {
  public:
   ShellAppDelegate();
   ~ShellAppDelegate() override;
 
   // AppDelegate overrides:
   void InitWebContents(content::WebContents* web_contents) override;
   void ResizeWebContents(content::WebContents* web_contents,
                          const gfx::Size& size) override;
   content::WebContents* OpenURLFromTab(
       content::BrowserContext* context,
@@ skipping 17 matching lines @@
   bool CheckMediaAccessPermission(content::WebContents* web_contents,
                                   const GURL& security_origin,
                                   content::MediaStreamType type,
                                   const Extension* extension) override;
   int PreferredIconSize() override;
   void SetWebContentsBlocked(content::WebContents* web_contents,
                              bool blocked) override;
   bool IsWebContentsVisible(content::WebContents* web_contents) override;
   void SetTerminatingCallback(const base::Closure& callback) override;
 
+  // content::WebContentsObserver:
+  void RenderViewCreated(content::RenderViewHost* render_view_host) override;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ShellAppDelegate);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_SHELL_BROWSER_SHELL_APP_DELEGATE_H_