stagefright: don't use ALooperRoster mutex for reply handling

Change replyID-s from uint32_t to an object
Move reply handling into the loopers (to reuse a common mutex)

Bug: 19607784
Change-Id: Iaa035b846c424c5687ed17ce1079b325e86c54be
diff --git a/media/libmediaplayerservice/nuplayer/RTSPSource.cpp b/media/libmediaplayerservice/nuplayer/RTSPSource.cpp
index 57d9ab2..5210fc8 100644
--- a/media/libmediaplayerservice/nuplayer/RTSPSource.cpp
+++ b/media/libmediaplayerservice/nuplayer/RTSPSource.cpp
@@ -311,7 +311,7 @@
 
 void NuPlayer::RTSPSource::onMessageReceived(const sp<AMessage> &msg) {
     if (msg->what() == kWhatDisconnect) {
-        uint32_t replyID;
+        sp<AReplyToken> replyID;
         CHECK(msg->senderAwaitsResponse(&replyID));
 
         mDisconnectReplyID = replyID;