frameworks/av: Hotword for pre-kitkat audio blobs

Christian Hoffman posted this change that might enable
hotword detection on pre kitkat audio blobs.

It would be interesting to see if this is working.

Not yet tested.

Thank you Christian

Change-Id: I8128abb9c2f4985454504beb44598d7c5158171e
libstagefright: Fix video encoder input buffer

Ported from cm10, needed to avoid the encoder eating up all input buffers,
which leaves no buffer left for the camera sometimes

Change-Id: I0432cd87a9defd08725ac8831d7376edb98d7e18