[Media Router] Set initial sink availability to available in MRMojoImpl.

chrome/browser/media/router/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/media_router_mojo_impl.h"
 
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
@@ skipping 73 matching lines @@
                    [](const media_router::MediaRoute& route) {
                       return route.is_local(); }) !=
       routes.end();
 
   // |this| will be deleted in UpdateHasLocalRoute() if |has_local_route| is
   // false. Note that ObserverList supports removing an observer while
   // iterating through it.
   router_->UpdateHasLocalRoute(has_local_route);
 }
 
-// TODO(mfoltz): Flip the default sink availability to UNAVAILABLE, once the
-// MRPM sends initial availability status.
 MediaRouterMojoImpl::MediaRouterMojoImpl(
     extensions::EventPageTracker* event_page_tracker)
     : event_page_tracker_(event_page_tracker),
       instance_id_(base::GenerateGUID()),
       has_local_route_(false),
-      availability_(interfaces::MediaRouter::SINK_AVAILABILITY_AVAILABLE),
+      availability_(interfaces::MediaRouter::SINK_AVAILABILITY_UNAVAILABLE),
       wakeup_attempt_count_(0),
       weak_factory_(this) {
   DCHECK(event_page_tracker_);
 }
 
 MediaRouterMojoImpl::~MediaRouterMojoImpl() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // Make sure |routes_observer_| is destroyed first, because it triggers
   // additional cleanup logic in this class that depends on other fields.
@@ skipping 668 matching lines @@
 }
 
 void MediaRouterMojoImpl::DrainPendingRequests() {
   DLOG_WITH_INSTANCE(ERROR)
       << "Draining request queue. (queue-length=" << pending_requests_.size()
       << ")";
   pending_requests_.clear();
 }
 
 }  // namespace media_router