rename AudioSystem::newAudioSessionId()

Rename AudioSystem::newAudioSessionId() to
AudioSystem::newAudioUniqueId() as it can be used
also for I/O handles.

Bug: 12378680.
Change-Id: I611ea3b5eb57a4b0774437f477ee87dc4ccc2cc2
diff --git a/media/libmedia/mediaplayer.cpp b/media/libmedia/mediaplayer.cpp
index 2b7ea97..6cd377a 100644
--- a/media/libmedia/mediaplayer.cpp
+++ b/media/libmedia/mediaplayer.cpp
@@ -59,7 +59,7 @@
     mLeftVolume = mRightVolume = 1.0;
     mVideoWidth = mVideoHeight = 0;
     mLockThreadId = 0;
-    mAudioSessionId = AudioSystem::newAudioSessionId();
+    mAudioSessionId = AudioSystem::newAudioUniqueId();
     AudioSystem::acquireAudioSessionId(mAudioSessionId, -1);
     mSendLevel = 0;
     mRetransmitEndpointValid = false;