Revert "Allows the authoring engine to skip frame."

o Skipping frames could lead to a lot of issues such as I frames is lost etc.
  It is not being used anyway.

This reverts commit 53d4e0d5.

Conflicts:

	media/libstagefright/AudioSource.cpp
	media/libstagefright/CameraSource.cpp

Change-Id: I3abba1647de48db25bdc369066eb2a7ae4dedec2