[Athena: Cleanup] consolidate ChromeAppActivity and ShellAppActivity

athena/content/shell/shell_app_activity.cc

-// 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.
-
-#include "athena/content/shell/shell_app_activity.h"
-
-#include "content/public/browser/web_contents.h"
-#include "extensions/browser/app_window/app_window.h"
-#include "extensions/browser/app_window/native_app_window.h"
-#include "ui/views/controls/webview/webview.h"
-
-namespace athena {
-
-ShellAppActivity::ShellAppActivity(extensions::AppWindow* app_window)
-    : AppActivity(app_window->extension_id()), app_window_(app_window) {
-  DCHECK(app_window_);
-}
-
-ShellAppActivity::~ShellAppActivity() {
-  app_window_->GetBaseWindow()->Close();  // Deletes |app_window_|.
-}
-
-views::Widget* ShellAppActivity::CreateWidget() {
-  return NULL;  // Use default widget.
-}
-
-views::WebView* ShellAppActivity::GetWebView() {
-  content::WebContents* web_contents = app_window_->web_contents();
-  views::WebView* web_view =
-      new views::WebView(web_contents->GetBrowserContext());
-  web_view->SetWebContents(web_contents);
-  Observe(web_contents);
-  return web_view;
-}
-
-}  // namespace athena