Add missing (and remove superfluous) 'explicit' from constructors.

content/renderer/media/peer_connection_handler_base.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_MEDIA_PEER_CONNECTION_HANDLER_BASE_H_
 #define CONTENT_RENDERER_MEDIA_PEER_CONNECTION_HANDLER_BASE_H_
 
 #include <map>
 #include <string>
 
 #include "base/memory/ref_counted.h"
 #include "base/message_loop_proxy.h"
 #include "content/common/content_export.h"
 #include "third_party/libjingle/source/talk/app/webrtc/mediastream.h"
 #include "third_party/libjingle/source/talk/app/webrtc/peerconnectioninterface.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebMediaStreamDescriptor.h"
 
 namespace content {
 class MediaStreamDependencyFactory;
 
 // PeerConnectionHandlerBase is the base class of a delegate for the
 // PeerConnection API messages going between WebKit and native
 // PeerConnection in libjingle.
 class CONTENT_EXPORT PeerConnectionHandlerBase
     : NON_EXPORTED_BASE(public webrtc::PeerConnectionObserver) {
  public:
-  PeerConnectionHandlerBase(
+  explicit PeerConnectionHandlerBase(
       MediaStreamDependencyFactory* dependency_factory);
 
  protected:
   virtual ~PeerConnectionHandlerBase();
 
   void AddStream(const WebKit::WebMediaStreamDescriptor& stream);
   bool AddStream(const WebKit::WebMediaStreamDescriptor& stream,
                  const webrtc::MediaConstraintsInterface* constraints);
   void RemoveStream(const WebKit::WebMediaStreamDescriptor& stream);
   WebKit::WebMediaStreamDescriptor CreateWebKitStreamDescriptor(
@@ skipping 17 matching lines @@
   // The message loop we are created on and on which to make calls to WebKit.
   // This should be the render thread message loop.
   scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
 
   DISALLOW_COPY_AND_ASSIGN(PeerConnectionHandlerBase);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_PEER_CONNECTION_HANDLER_BASE_H_