Added stub MediaSourcePlayer for developing behind the flag

content/browser/media/android/browser_demuxer_android.cc

Index: content/browser/media/android/browser_demuxer_android.cc
diff --git a/content/browser/media/android/browser_demuxer_android.cc b/content/browser/media/android/browser_demuxer_android.cc
index ed462032fdd7f6ad3d278996d36ae4009370ecca..5ba4fcb4a109fb2ff7976b82a28fa466c63bcfc0 100644
--- a/content/browser/media/android/browser_demuxer_android.cc
+++ b/content/browser/media/android/browser_demuxer_android.cc
@@ -4,7 +4,10 @@
 
 #include "content/browser/media/android/browser_demuxer_android.h"
 
+#include "base/command_line.h"
 #include "content/common/media/media_player_messages_android.h"
+#include "media/base/android/mt/player.h"
+#include "media/base/media_switches.h"
 
 namespace content {
 
@@ -42,7 +45,7 @@ class BrowserDemuxerAndroid::Internal : public media::DemuxerAndroid {
  private:
   // Helper for DCHECKing that the ID is still registered.
   bool ClientIDExists() {
-    return demuxer_->demuxer_clients_.Lookup(demuxer_client_id_);
+    return demuxer_->Lookup(demuxer_client_id_);
   }
 
   scoped_refptr<BrowserDemuxerAndroid> demuxer_;
@@ -52,13 +55,21 @@ class BrowserDemuxerAndroid::Internal : public media::DemuxerAndroid {
 };
 
 BrowserDemuxerAndroid::BrowserDemuxerAndroid()
-    : BrowserMessageFilter(MediaPlayerMsgStart) {}
+    : BrowserMessageFilter(MediaPlayerMsgStart) {
+  enable_media_player_v2_ =
+      base::CommandLine::ForCurrentProcess()->
+      HasSwitch(switches::kEnableMediaPlayerV2);
+
+}
 
 BrowserDemuxerAndroid::~BrowserDemuxerAndroid() {}
 
 void BrowserDemuxerAndroid::OverrideThreadForMessage(
     const IPC::Message& message,
     BrowserThread::ID* thread) {
+  if (enable_media_player_v2_)
+    return; // keep default BrowserThread::IO
+
   switch (message.type()) {
     case MediaPlayerHostMsg_DemuxerReady::ID:
     case MediaPlayerHostMsg_ReadFromDemuxerAck::ID:
@@ -71,6 +82,31 @@ void BrowserDemuxerAndroid::OverrideThreadForMessage(
 
 bool BrowserDemuxerAndroid::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
+
+  if (enable_media_player_v2_) {
+    // Redirect demuxer messages to Media thread
+    if (!media::mt::GetMediaTaskRunner()->BelongsToCurrentThread()) {
+      media::mt::GetMediaTaskRunner()->PostTask(
+          FROM_HERE,
+          base::Bind(
+              base::IgnoreResult(&BrowserDemuxerAndroid::OnMessageReceived),
+              this, message));
+
+      switch(message.type()) {
+        case MediaPlayerHostMsg_DemuxerReady::ID:
+        case MediaPlayerHostMsg_ReadFromDemuxerAck::ID:
+        case MediaPlayerHostMsg_DurationChanged::ID:
+        case MediaPlayerHostMsg_DemuxerSeekDone::ID:
+          handled = true;
+          break;
+        default:
+          handled = false;
+          break;
+      }
+      return handled;
+    }
+  }
+
   IPC_BEGIN_MESSAGE_MAP(BrowserDemuxerAndroid, message)
     IPC_MESSAGE_HANDLER(MediaPlayerHostMsg_DemuxerReady, OnDemuxerReady)
     IPC_MESSAGE_HANDLER(MediaPlayerHostMsg_ReadFromDemuxerAck,
@@ -95,20 +131,29 @@ void BrowserDemuxerAndroid::AddDemuxerClient(
     media::DemuxerAndroidClient* client) {
   DVLOG(1) << __FUNCTION__ << " peer_pid=" << peer_pid()
            << " demuxer_client_id=" << demuxer_client_id;
+
+  base::AutoLock lock(lock_);
   demuxer_clients_.AddWithID(client, demuxer_client_id);
 }
 
 void BrowserDemuxerAndroid::RemoveDemuxerClient(int demuxer_client_id) {
   DVLOG(1) << __FUNCTION__ << " peer_pid=" << peer_pid()
            << " demuxer_client_id=" << demuxer_client_id;
+
+  base::AutoLock lock(lock_);
   demuxer_clients_.Remove(demuxer_client_id);
 }
 
+media::DemuxerAndroidClient*
+BrowserDemuxerAndroid::Lookup(int demuxer_client_id) {
+  base::AutoLock lock(lock_);
+  return demuxer_clients_.Lookup(demuxer_client_id);
+}
+
 void BrowserDemuxerAndroid::OnDemuxerReady(
     int demuxer_client_id,
     const media::DemuxerConfigs& configs) {
-  media::DemuxerAndroidClient* client =
-      demuxer_clients_.Lookup(demuxer_client_id);
+  media::DemuxerAndroidClient* client = Lookup(demuxer_client_id);
   if (client)
     client->OnDemuxerConfigsAvailable(configs);
 }
@@ -116,8 +161,7 @@ void BrowserDemuxerAndroid::OnDemuxerReady(
 void BrowserDemuxerAndroid::OnReadFromDemuxerAck(
     int demuxer_client_id,
     const media::DemuxerData& data) {
-  media::DemuxerAndroidClient* client =
-      demuxer_clients_.Lookup(demuxer_client_id);
+  media::DemuxerAndroidClient* client = Lookup(demuxer_client_id);
   if (client)
     client->OnDemuxerDataAvailable(data);
 }
@@ -125,16 +169,14 @@ void BrowserDemuxerAndroid::OnReadFromDemuxerAck(
 void BrowserDemuxerAndroid::OnDemuxerSeekDone(
     int demuxer_client_id,
     const base::TimeDelta& actual_browser_seek_time) {
-  media::DemuxerAndroidClient* client =
-      demuxer_clients_.Lookup(demuxer_client_id);
+  media::DemuxerAndroidClient* client = Lookup(demuxer_client_id);
   if (client)
     client->OnDemuxerSeekDone(actual_browser_seek_time);
 }
 
 void BrowserDemuxerAndroid::OnDurationChanged(int demuxer_client_id,
                                               const base::TimeDelta& duration) {
-  media::DemuxerAndroidClient* client =
-      demuxer_clients_.Lookup(demuxer_client_id);
+  media::DemuxerAndroidClient* client = Lookup(demuxer_client_id);
   if (client)
     client->OnDemuxerDurationChanged(duration);
 }