[PresentationAPI] Plumbing |onstatechange| event for the PresentationSession from Blink to platform/

Source/modules/presentation/PresentationController.cpp

 // 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.
 
 #include "config.h"
 #include "modules/presentation/PresentationController.h"
 
 #include "core/frame/LocalFrame.h"
 #include "modules/presentation/PresentationSession.h"
 #include "public/platform/modules/presentation/WebPresentationClient.h"
@@ skipping 68 matching lines @@
 {
     if (!m_presentation) {
         PresentationSession::dispose(sessionClient);
         return;
     }
 
     PresentationSession* session = PresentationSession::take(sessionClient, m_presentation);
     m_presentation->didStartDefaultSession(session);
 }
 
+void PresentationController::didChangeSessionState(WebPresentationSessionClient* sessionClient, WebPresentationSessionClient::SessionState state)
+{
+    if (m_presentation) {
+        PresentationSession* session = m_presentation->findSession(sessionClient);

[Peter Beverloo, 2015/03/20 19:07:40]

Do you expect more events following this paradigm? Otherwise you could avoid
exposing something like findSession() in favor of following the rest of your
plumbing, e.g. isAvailableChangeWatched().


if (m_presentation)
    m_presentation->didChangeSessionState(sessionClient, state);

[whywhat, 2015/03/23 21:12:16]

Yes, there will be at least an event about receiving a message. I can move
findSession to the private section of Presentation class though and follow the
pattern of delegating to Presentation.

+        if (session)
+            session->didChangeState(state);
+    }
+
+    PresentationSession::dispose(sessionClient);
+}
+
 void PresentationController::startSession(const String& presentationUrl, const String& presentationId, WebPresentationSessionClientCallbacks* callbacks)
 {
     if (!m_client) {
         delete callbacks;
         return;
     }
     m_client->startSession(presentationUrl, presentationId, callbacks);
 }
 
 void PresentationController::joinSession(const String& presentationUrl, const String& presentationId, WebPresentationSessionClientCallbacks* callbacks)
@@ skipping 19 matching lines @@
 
 void PresentationController::willDetachFrameHost()
 {
     if (m_client) {
         m_client->setController(nullptr);
         m_client = nullptr;
     }
 }
 
 } // namespace blink