Put the Pepper stuff in the content namespace.

content/renderer/pepper/pepper_device_enumeration_event_handler.h

 // 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.
 
 #ifndef CONTENT_RENDERER_PEPPER_PEPPER_DEVICE_ENUMERATION_EVENT_HANDLER_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_DEVICE_ENUMERATION_EVENT_HANDLER_H_
 
 #include <map>
 
 #include "base/memory/weak_ptr.h"
 #include "content/renderer/media/media_stream_dispatcher_eventhandler.h"
 #include "content/renderer/pepper/pepper_plugin_delegate_impl.h"
 #include "webkit/plugins/ppapi/plugin_delegate.h"
 
+namespace content {
+
 class PepperDeviceEnumerationEventHandler
     : public MediaStreamDispatcherEventHandler,
       public base::SupportsWeakPtr<PepperDeviceEnumerationEventHandler> {
  public:
   PepperDeviceEnumerationEventHandler();
   virtual ~PepperDeviceEnumerationEventHandler();
 
   int RegisterEnumerateDevicesCallback(
       const webkit::ppapi::PluginDelegate::EnumerateDevicesCallback& callback);
 
@@ skipping 44 matching lines @@
       EnumerateCallbackMap;
   EnumerateCallbackMap enumerate_callbacks_;
 
   typedef std::map<int, PepperPluginDelegateImpl::OpenDeviceCallback>
       OpenCallbackMap;
   OpenCallbackMap open_callbacks_;
 
   DISALLOW_COPY_AND_ASSIGN(PepperDeviceEnumerationEventHandler);
 };
 
+}  // namespace content
+
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_DEVICE_ENUMERATION_EVENT_HANDLER_H_