[Presentation API] Plumbing the |defaultpresentationstart| event from Blink to browser/Mojo.

content/renderer/presentation/presentation_dispatcher.cc

 // 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 "content/renderer/presentation/presentation_dispatcher.h"
 
 #include "base/logging.h"
 #include "content/common/presentation/presentation_service.mojom.h"
 #include "content/public/common/service_registry.h"
 #include "content/public/renderer/render_frame.h"
@@ skipping 95 matching lines @@
 void PresentationDispatcher::OnScreenAvailabilityChanged(bool available) {
   if (!controller_)
     return;
 
   // Reset the callback to get the next event.
   updateAvailableChangeWatched(controller_->isAvailableChangeWatched());
 
   controller_->didChangeAvailability(available);
 }
 
+void PresentationDispatcher::OnDefaultSessionStarted(
+    presentation::PresentationSessionInfoPtr session_info) {
+  if (!controller_)
+    return;
+
+  // Reset the callback to get the next event.
+  presentation_service_->ListenForDefaultSessionStart(base::Bind(
+      &PresentationDispatcher::OnDefaultSessionStarted,
+      base::Unretained(this)));
+
+  DCHECK(!session_info.is_null());
+  PresentationSessionDispatcher* session_dispatcher =
+      new PresentationSessionDispatcher(session_info.Pass());
+  presentation_session_dispatchers_.push_back(session_dispatcher);
+  controller_->didStartDefaultSession(
+      new PresentationSessionClient(session_dispatcher));
+}
+
 void PresentationDispatcher::OnSessionCreated(
     blink::WebPresentationSessionClientCallbacks* callback,
     presentation::PresentationSessionInfoPtr session_info,
     presentation::PresentationErrorPtr error) {
   DCHECK(callback);
   if (!error.is_null()) {
     DCHECK(session_info.is_null());
     callback->onError(new blink::WebPresentationError(
         GetWebPresentationErrorTypeFromMojo(error->errorType),
         blink::WebString::fromUTF8(error->message)));
     return;
   }
 
   DCHECK(!session_info.is_null());
   PresentationSessionDispatcher* session_dispatcher =
       new PresentationSessionDispatcher(session_info.Pass());
   presentation_session_dispatchers_.push_back(session_dispatcher);
   callback->onSuccess(new PresentationSessionClient(session_dispatcher));
 }
 
 void PresentationDispatcher::ConnectToPresentationServiceIfNeeded() {
   if (presentation_service_.get())
     return;
 
   render_frame()->GetServiceRegistry()->ConnectToRemoteService(
       &presentation_service_);
+  presentation_service_->ListenForDefaultSessionStart(base::Bind(
+      &PresentationDispatcher::OnDefaultSessionStarted,
+      base::Unretained(this)));
 }
 
 }  // namespace content