Move render_view_context_menu.* related files out of tab_contents.

chrome/browser/tab_contents/render_view_context_menu_observer.cc

-// Copyright (c) 2011 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/tab_contents/render_view_context_menu_observer.h"
-
-void RenderViewContextMenuObserver::InitMenu(
-    const content::ContextMenuParams& params) {
-}
-
-bool RenderViewContextMenuObserver::IsCommandIdSupported(int command_id) {
-  return false;
-}
-
-bool RenderViewContextMenuObserver::IsCommandIdChecked(int command_id) {
-  return false;
-}
-
-bool RenderViewContextMenuObserver::IsCommandIdEnabled(int command_id) {
-  return false;
-}
-
-void RenderViewContextMenuObserver::ExecuteCommand(int command_id) {
-}
-
-void RenderViewContextMenuObserver::OnMenuCancel() {
-}