[Presentation API] (5th) (1-UA) integrate controller and receiver side for 1-UA messaging

chrome/browser/media/router/offscreen_presentation_manager.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 "chrome/browser/media/router/offscreen_presentation_manager.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "content/public/browser/render_frame_host.h"
@@ skipping 43 matching lines @@
   DVLOG(2) << __FUNCTION__ << " [presentation_id]: " << presentation_id
            << ", [render_frame_host_id]: " << render_frame_host_id.second;
   DCHECK(thread_checker_.CalledOnValidThread());
 
   auto it = offscreen_presentations_.find(presentation_id);
   if (it == offscreen_presentations_.end())
     return;
 
   // Remove presentation if no controller and receiver.
   it->second->UnregisterController(render_frame_host_id);
-  if (it->second->pending_controllers_.size() == 0 &&
-      it->second->receiver_callback_.is_null())
+  if (!it->second->IsValid()) {
+    DLOG(WARNING) << __func__ << " no receiver callback has been registered to "
+                  << "[presentation_id]: " << presentation_id;
     offscreen_presentations_.erase(presentation_id);
+  }
 }
 
 void OffscreenPresentationManager::OnOffscreenPresentationReceiverCreated(
     const std::string& presentation_id,
     const GURL& presentation_url,
     const content::ReceiverConnectionAvailableCallback& receiver_callback) {
   DVLOG(2) << __FUNCTION__ << " [presentation_id]: " << presentation_id;
   DCHECK(thread_checker_.CalledOnValidThread());
   auto presentation =
       GetOrCreateOffscreenPresentation(presentation_id, presentation_url);
@@ skipping 45 matching lines @@
   }
   receiver_callback_ = receiver_callback;
   pending_controllers_.clear();
 }
 
 bool OffscreenPresentationManager::OffscreenPresentation::IsValid() {
   return !(pending_controllers_.size() == 0 && receiver_callback_.is_null());
 }
 
 }  // namespace media_router