Change the launcher to create new tabs instead of windows when

ash/shell/launcher_delegate_impl.h

 // 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.
 
 #ifndef ASH_SHELL_LAUNCHER_DELEGATE_IMPL_H_
 #define ASH_SHELL_LAUNCHER_DELEGATE_IMPL_H_
 #pragma once
 
 #include "ash/launcher/launcher_delegate.h"
 #include "base/compiler_specific.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
 namespace shell {
 
 class WindowWatcher;
 
 class LauncherDelegateImpl : public ash::LauncherDelegate {
  public:
   explicit LauncherDelegateImpl(WindowWatcher* watcher);
   virtual ~LauncherDelegateImpl();
 
   void set_watcher(WindowWatcher* watcher) { watcher_ = watcher; }
 
   // LauncherDelegate overrides:
-  virtual void CreateNewWindow() OVERRIDE;
+  virtual void CreateNewTab() OVERRIDE;
   virtual void ItemClicked(const ash::LauncherItem& item) OVERRIDE;
   virtual int GetBrowserShortcutResourceId() OVERRIDE;
   virtual string16 GetTitle(const ash::LauncherItem& item) OVERRIDE;
   virtual ui::MenuModel* CreateContextMenu(
       const ash::LauncherItem& item) OVERRIDE;
   virtual ash::LauncherID GetIDByWindow(aura::Window* window) OVERRIDE;
 
  private:
   // Used to update Launcher. Owned by main.
   WindowWatcher* watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(LauncherDelegateImpl);
 };
 
 }  // namespace shell
 }  // namespace ash
 
 #endif  // ASH_SHELL_LAUNCHER_DELEGATE_IMPL_H_