MediaRecorder: Add pause interface

- add pause in java level
- add pause in jni level

CRs-Fixed: 587051

Add 2 APIs (suspend/resume) in MediaPlayer

- API:suspend() will just pause the player and release all the decoders
  to replace release() which will release the whole player
- API:resume() will just init the decoders again,
  then start() will be called to start to play the streaming

Change-Id: Ia0c38bd827f21261b2bd87c04778e86362003344