More source code Clean up in video editor engine

o fixed incorrect design and got rid of PreviewPlayerBase class
o removed obsolete/unused code as much as possible and reformatted the source code
o verified and passed functional tests
o More to come ...

Change-Id: I7a89162f8b9d9ea6eabcf0457366cd2f6d970d11
diff --git a/libvideoeditor/lvpp/AudioPlayerBase.cpp b/libvideoeditor/lvpp/AudioPlayerBase.cpp
index b45f9bf..67ea43c 100644
--- a/libvideoeditor/lvpp/AudioPlayerBase.cpp
+++ b/libvideoeditor/lvpp/AudioPlayerBase.cpp
@@ -27,13 +27,13 @@
 #include <media/stagefright/MetaData.h>
 
 #include "AudioPlayerBase.h"
-#include "PreviewPlayerBase.h"
+#include "PreviewPlayer.h"
 
 namespace android {
 
 AudioPlayerBase::AudioPlayerBase(
         const sp<MediaPlayerBase::AudioSink> &audioSink,
-        PreviewPlayerBase *observer)
+        PreviewPlayer *observer)
     : mAudioTrack(NULL),
       mInputBuffer(NULL),
       mSampleRate(0),