libgui: Bring back support for mHeap-based screenshots

Older graphics libraries throw a hissy fit when trying to lock
buffers for Surface-based screenshots, on at least Tegra2/3 and
Exynos4 hardware.

This patch depends on the BOARD_USE_MHEAP_SCREENSHOT board flag
and requires the ro.bq.gpu_to_cpu_unsupported property set to 1
in order to work.

Change-Id: I7db955e2cdd120018e349c14290e975788e70ed3
Merge "libgui: Bring back support for mHeap-based screenshots" into cm-11.0
surfaceflinger: don't handle EVENT_ORIENTATION when !HWC_DEVICE_API_VERSION_1_0

a184463 causes segfault on boot for the enrc2b (and probably others), this fixes it.

Change-Id: Ic4a7a05b44c8cc44a0d25c56def4acdf5b0939df
Merge remote-tracking branch 'cm/cm-11.0' into cm-11.0