[Media Router] Connection state change listening redesign part 2.

content/public/browser/presentation_service_delegate.h

 // Copyright 2015 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_PUBLIC_BROWSER_PRESENTATION_SERVICE_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_PRESENTATION_SERVICE_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/presentation_session.h"
 #include "content/public/browser/presentation_session_message.h"
 
 namespace content {
 
 class PresentationScreenAvailabilityListener;
 
 using PresentationSessionStartedCallback =
     base::Callback<void(const PresentationSessionInfo&)>;
 using PresentationSessionErrorCallback =
     base::Callback<void(const PresentationError&)>;
-using SessionStateChangedCallback =
+using PresentationConnectionStateChangedCallback =
     base::Callback<void(const PresentationSessionInfo&,
                         PresentationConnectionState)>;
 
 // Param #0: a vector of messages that are received.
 // Param #1: tells the callback handler that it may reuse strings or buffers
 //           in the messages contained within param #0.
 using PresentationSessionMessageCallback = base::Callback<
     void(const ScopedVector<content::PresentationSessionMessage>&, bool)>;
 
 // An interface implemented by embedders to handle presentation API calls
@@ skipping 124 matching lines @@
   // |session|: The presentation session to send the message to.
   // |message|: The message to send. The embedder takes ownership of |message|.
   //            Must not be null.
   // |send_message_cb|: Invoked after handling the send message request.
   virtual void SendMessage(int render_process_id,
                            int render_frame_id,
                            const content::PresentationSessionInfo& session,
                            scoped_ptr<PresentationSessionMessage> message,
                            const SendMessageCallback& send_message_cb) = 0;
 
-  // Continuously listen for presentation session state changes for a frame.
+  // Continuously listen for state changes for a PresentationConnection in a
+  // frame.
   // |render_process_id|, |render_frame_id|: ID of frame.
-  // |state_changed_cb|: Invoked with the session and its new state whenever
-  // there is a state change.
-  virtual void ListenForSessionStateChange(
+  // |connection|: PresentationConnection to listen for state changes.
+  // |state_changed_cb|: Invoked with the PresentationConnection and its new
+  // state whenever there is a state change.
+  virtual void ListenForConnectionStateChange(
       int render_process_id,
       int render_frame_id,
-      const SessionStateChangedCallback& state_changed_cb) = 0;
+      const PresentationSessionInfo& connection,
+      const PresentationConnectionStateChangedCallback& state_changed_cb) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_PRESENTATION_SERVICE_DELEGATE_H_