Abort surface composition if hw surface is invalid

If an invalid display device is detected during surface composition
(e.g., a simulated secondary display is removed), abort the
composition.

Change-Id: Ia6afb2e287882d8ae0614eb25463d3f85b687adf
Configure dalvik heap parameters for low memory devices

Reduces after boot memory footprint by about 5-8MB
Note: This is for low memory based devices only (~512MB RAM
or less)

Change-Id: I4b4b9ae3efaff96551457e566bbb9bd4f0f23fd5