Remove unused shell_app_window_api.h/cc

apps/shell/browser/shell_app_window_api.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 APPS_SHELL_BROWSER_SHELL_APP_WINDOW_API_H_
-#define APPS_SHELL_BROWSER_SHELL_APP_WINDOW_API_H_
-
-#include "base/compiler_specific.h"
-#include "extensions/browser/extension_function.h"
-
-namespace extensions {
-
-// A simplified implementation of the chrome.app.window.create() function for
-// app_shell. Opens a fullscreen window and invokes the window callback. Most
-// of the response is stub data, but the JS contentWindow is valid.
-class ShellAppWindowCreateFunction : public AsyncExtensionFunction {
- public:
-  ShellAppWindowCreateFunction();
-
-  // Don't use the APP_WINDOW_CREATE histogram so we don't pollute the
-  // statistics for the real Chrome implementation.
-  DECLARE_EXTENSION_FUNCTION("app.window.create", UNKNOWN);
-
- private:
-  virtual ~ShellAppWindowCreateFunction();
-  virtual bool RunAsync() OVERRIDE;
-};
-
-}  // namespace extensions
-
-#endif  // APPS_SHELL_BROWSER_SHELL_APP_WINDOW_API_H_