media: Allow WMPI to send playing started notification while playing

content/browser/media/media_web_contents_observer.cc

 // Copyright 2014 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/browser/media/media_web_contents_observer.h"
 
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
 #include "build/build_config.h"
 #include "content/browser/media/audible_metrics.h"
@@ skipping 195 matching lines @@
   }
 
   // If there are no more video players, clear the video power save blocker.
   if (active_video_players_.empty())
     video_power_save_blocker_.reset();
 }
 
 void MediaWebContentsObserver::AddMediaPlayerEntry(
     const MediaPlayerId& id,
     ActiveMediaPlayerMap* player_map) {
-  DCHECK(std::find((*player_map)[id.first].begin(),
-                   (*player_map)[id.first].end(),
-                   id.second) == (*player_map)[id.first].end());
-  (*player_map)[id.first].push_back(id.second);
+  (*player_map)[id.first].insert(id.second);
 }
 
 bool MediaWebContentsObserver::RemoveMediaPlayerEntry(
     const MediaPlayerId& id,
     ActiveMediaPlayerMap* player_map) {
   auto it = player_map->find(id.first);
   if (it == player_map->end())
     return false;
 
   // Remove the player.
-  auto player_for_removal =
-      std::remove(it->second.begin(), it->second.end(), id.second);
-  if (player_for_removal == it->second.end())
+  bool did_remove = it->second.erase(id.second) == 1;
+  if (!did_remove)
     return false;
-  it->second.erase(player_for_removal);
 
   // If there are no players left, remove the map entry.
   if (it->second.empty())
     player_map->erase(it);
 
   return true;
 }
 
 void MediaWebContentsObserver::RemoveAllMediaPlayerEntries(
     RenderFrameHost* render_frame_host,
     ActiveMediaPlayerMap* player_map,
     std::set<MediaPlayerId>* removed_players) {
   auto it = player_map->find(render_frame_host);
   if (it == player_map->end())
     return;
 
   for (int delegate_id : it->second)
     removed_players->insert(MediaPlayerId(render_frame_host, delegate_id));
 
   player_map->erase(it);
 }
 
 }  // namespace content