aura: Remove client::UserActionClient.

chrome/browser/ui/ash/user_action_handler.cc

-// 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 "chrome/browser/ui/ash/user_action_handler.h"
-
-#include "ash/wm/window_util.h"
-#include "chrome/browser/ui/browser.h"
-#include "chrome/browser/ui/browser_finder.h"
-#include "chrome/browser/ui/browser_window.h"
-#include "chrome/browser/ui/tabs/tab_strip_model.h"
-#include "content/public/browser/web_contents.h"
-
-// Returns the currently-active WebContents belonging to the active browser, or
-// NULL if there's no currently-active browser.
-content::WebContents* GetActiveWebContents() {
-  Browser* browser = chrome::FindLastActiveWithHostDesktopType(
-      chrome::HOST_DESKTOP_TYPE_ASH);
-  if (!browser)
-    return NULL;
-  if (!ash::wm::IsActiveWindow(browser->window()->GetNativeWindow()))
-    return NULL;
-
-  return browser->tab_strip_model()->GetActiveWebContents();
-}
-
-UserActionHandler::UserActionHandler() {}
-
-UserActionHandler::~UserActionHandler() {}
-
-bool UserActionHandler::OnUserAction(
-    aura::client::UserActionClient::Command command) {
-  switch (command) {
-    case aura::client::UserActionClient::BACK: {
-      content::WebContents* contents = GetActiveWebContents();
-      if (contents && contents->GetController().CanGoBack()) {
-        contents->GetController().GoBack();
-        return true;
-      }
-      break;
-    }
-    case aura::client::UserActionClient::FORWARD: {
-      content::WebContents* contents = GetActiveWebContents();
-      if (contents && contents->GetController().CanGoForward()) {
-        contents->GetController().GoForward();
-        return true;
-      }
-      break;
-    }
-    default:
-      break;
-  }
-  return false;
-}