Let Flash join and be controlled by media session

content/browser/media/session/pepper_web_contents_observer.cc

+// Copyright 2016 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/session/pepper_web_contents_observer.h"
+
+#include "base/feature_list.h"
+#include "base/logging.h"
+#include "content/browser/media/session/media_session.h"
+#include "content/browser/media/session/pepper_player_delegate.h"
+#include "content/common/frame_messages.h"
+#include "ipc/ipc_message_macros.h"
+#include "media/base/media_switches.h"
+
+namespace content {
+
+PepperWebContentsObserver::PepperWebContentsObserver(WebContents *web_contents)
+    : WebContentsObserver(web_contents) {}
+
+PepperWebContentsObserver::~PepperWebContentsObserver() = default;
+
+void PepperWebContentsObserver::WebContentsDestroyed() {
+  for (auto& instance_player : players_map_) {
+    OnPepperStopsPlayback(instance_player.first);
+  }
+}
+
+bool PepperWebContentsObserver::OnMessageReceived(
+    const IPC::Message& msg, RenderFrameHost* render_frame_host) {
+  if (!base::FeatureList::IsEnabled(media::kFlashJoinsMediaSession))
+    return true;
+
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP_WITH_PARAM(PepperWebContentsObserver, msg,
+                                   render_frame_host)
+      IPC_MESSAGE_HANDLER(FrameHostMsg_PepperStartsPlayback,
+                          OnPepperStartsPlayback)
+      IPC_MESSAGE_HANDLER(FrameHostMsg_PepperStopsPlayback,
+                          OnPepperStopsPlayback)
+      IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+
+  return handled;
+}
+
+void PepperWebContentsObserver::PepperInstanceCreated(int32_t pp_instance) {}
+
+void PepperWebContentsObserver::PepperInstanceDeleted(int32_t pp_instance) {
+  OnPepperStopsPlayback(pp_instance);
+}
+
+void PepperWebContentsObserver::OnPepperStartsPlayback(int32_t pp_instance) {
+  if (players_map_.count(pp_instance))
+    return;
+
+  players_map_[pp_instance].reset(new PepperPlayerDelegate(this, pp_instance));
+  MediaSession::Get(web_contents())->AddPlayer(
+      players_map_[pp_instance].get(), 0, MediaSession::Type::Content);
+}
+
+void PepperWebContentsObserver::OnPepperStopsPlayback(int32_t pp_instance) {
+  DCHECK_EQ(players_map_.count(pp_instance), 1u);
+
+  // Only remove the player from MediaSession once the Pepper instance
+  // is deleted.
+  if (players_map_.count(pp_instance)) {
+    MediaSession::Get(web_contents())->RemovePlayer(
+        players_map_[pp_instance].get(), 0);
+  }
+
+  players_map_.erase(pp_instance);

[jochen (gone - plz use gerrit), 2016/06/27 11:47:11]

why is this not in the previous if?

[Zhiqiang Zhang (Slow), 2016/06/28 18:53:24]

Sorry, this is code in an old patch. Fixed.

+}
+
+}  // namespace content