Move ExtensionHost into extensions namespace

chrome/browser/extensions/extension_host_mac.mm

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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/extensions/extension_host_mac.h"
 
 #import "chrome/browser/ui/cocoa/chrome_event_processing_window.h"
 #import "chrome/browser/ui/cocoa/extensions/extension_popup_controller.h"
 #import "chrome/browser/ui/cocoa/info_bubble_window.h"
 #include "chrome/common/view_type.h"
 #include "content/public/browser/native_web_keyboard_event.h"
 
 using content::NativeWebKeyboardEvent;
 
+namespace extensions {
+
 ExtensionHostMac::~ExtensionHostMac() {
   // If there is a popup open for this host's extension, close it.
   ExtensionPopupController* popup = [ExtensionPopupController popup];
   if ([[popup window] isVisible] &&
       [popup extensionHost]->extension() == this->extension()) {
     InfoBubbleWindow* window = (InfoBubbleWindow*)[popup window];
     [window setDelayOnClose:NO];
     [popup close];
   }
 }
 
 void ExtensionHostMac::UnhandledKeyboardEvent(
     const NativeWebKeyboardEvent& event) {
   if (event.skip_in_browser || event.type == NativeWebKeyboardEvent::Char ||
       extension_host_type() != chrome::VIEW_TYPE_EXTENSION_POPUP) {
     return;
   }
 
   ChromeEventProcessingWindow* event_window =
       static_cast<ChromeEventProcessingWindow*>([view()->native_view() window]);
   DCHECK([event_window isKindOfClass:[ChromeEventProcessingWindow class]]);
   [event_window redispatchKeyEvent:event.os_event];
 }
+
+}  // namespace extensions