[Presentation API] Added the DefaultPresentationStart event and parsing of the default presentation…

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"
 
 namespace blink {
 
 PresentationController::PresentationController(LocalFrame& frame, WebPresentationClient* client)
     : FrameDestructionObserver(&frame)
     , m_client(client)
 {
     if (m_client)
         m_client->setController(this);
@@ skipping 48 matching lines @@
         return false;
     return m_presentation->isAvailableChangeWatched();
 }
 
 void PresentationController::updateAvailableChangeWatched(bool watched)
 {
     if (m_client)
         m_client->updateAvailableChangeWatched(watched);
 }
 
+void PresentationController::didStartDefaultSession(WebPresentationSessionClient* sessionClient)
+{
+    if (!m_presentation) {
+        PresentationSession::dispose(sessionClient);
+        return;
+    }
+
+    PresentationSession* session = PresentationSession::take(sessionClient, m_presentation);
+    m_presentation->didStartDefaultSession(session);
+}
+
 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 12 matching lines @@
 
 void PresentationController::willDetachFrameHost()
 {
     if (m_client) {
         m_client->setController(nullptr);
         m_client = nullptr;
     }
 }
 
 } // namespace blink