[Media Router] Wire through a new MRPM call to update media sinks.

chrome/browser/media/router/mojo/media_router_mojo_impl.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/mojo/media_router_mojo_impl.h"
 
 #include <stddef.h>
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/scoped_vector.h"
 #include "base/observer_list.h"
 #include "base/stl_util.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/media/router/issues_observer.h"
 #include "chrome/browser/media/router/media_router_factory.h"
 #include "chrome/browser/media/router/media_routes_observer.h"
 #include "chrome/browser/media/router/media_sinks_observer.h"
+#include "chrome/browser/media/router/media_source_helper.h"
 #include "chrome/browser/media/router/mojo/media_route_provider_util_win.h"
 #include "chrome/browser/media/router/mojo/media_router_mojo_metrics.h"
 #include "chrome/browser/media/router/mojo/media_router_type_converters.h"
 #include "chrome/browser/media/router/presentation_session_messages_observer.h"
 #include "chrome/browser/sessions/session_tab_helper.h"
 #include "extensions/browser/process_manager.h"
 
 #define DVLOG_WITH_INSTANCE(level) \
   DVLOG(level) << "MR #" << instance_id_ << ": "
 
@@ skipping 389 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
   issue_manager_.AddIssue(issue);
 }
 
 void MediaRouterMojoImpl::ClearIssue(const Issue::Id& issue_id) {
   DCHECK(thread_checker_.CalledOnValidThread());
   issue_manager_.ClearIssue(issue_id);
 }
 
 void MediaRouterMojoImpl::OnUserGesture() {
+  // Allow MRPM to intelligently update sinks and observers by passing in a
+  // media source.

[mark a. foltz, 2016/04/22 22:20:38]

I think some comment here about why we're discovering specifically for the
desktop source would be helpful.

+  UpdateMediaSinks(MediaSourceForDesktop().id());
+
 #if defined(OS_WIN)
   EnsureMdnsDiscoveryEnabled();
 #endif
 }
 
 bool MediaRouterMojoImpl::RegisterMediaSinksObserver(
     MediaSinksObserver* observer) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // Create an observer list for the media source and add |observer|
@@ skipping 539 matching lines @@
   }
 }
 
 void MediaRouterMojoImpl::OnFirewallCheckComplete(
     bool firewall_can_use_local_ports) {
   if (firewall_can_use_local_ports)
     EnsureMdnsDiscoveryEnabled();
 }
 #endif
 
+void MediaRouterMojoImpl::UpdateMediaSinks(
+    const MediaSource::Id& source_id) {
+  SetWakeReason(MediaRouteProviderWakeReason::UPDATE_MEDIA_SINKS);

[mark a. foltz, 2016/04/22 22:20:38]

We should see wakeups < the number of times the dialog is opened.

+  RunOrDefer(base::Bind(&MediaRouterMojoImpl::DoUpdateMediaSinks,
+                        base::Unretained(this), source_id));
+}
+
+void MediaRouterMojoImpl::DoUpdateMediaSinks(
+    const MediaSource::Id& source_id) {
+  DVLOG_WITH_INSTANCE(1) << "DoUpdateMediaSinks" << source_id;
+  media_route_provider_->UpdateMediaSinks(source_id);
+}
+
 }  // namespace media_router