Add a freeMosaicMemory function in JNI to address the leaks.

1) Fix coding style issues.
2) Added native and java functions to freeMosaicMemory.
3) Added optimized YUV420to444 conversion routine to native side.
4) Fixed more style issues based on code review comments.

Change-Id: Ic824584f6b3a02e4d0d7b472bed57637873ca622
2 files changed