gui: Allow devices to disable fence sync

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: Ifecc7af579bfde9d0a7daaaf528ea0773ce6ceb2
DisplayDevice: Backwards compatibility with old EGL

From 4.1 to 4.2, the display subsystem was reworked to
use SurfaceTextureClient/BufferQueue instead of
FramebufferNativeWindow for the framebuffer itself.

Unfortunately, some legacy EGL libraries make assumptions
that any framebuffer device will be FramebufferNativeWindow.

These EGL libraries will fail when used in 4.2 as if the
framebuffer is not FramebufferNativeWindow, they will
try to dequeue more than one buffer at a time, which
will cause a hang of the graphics subsystem.

This allows use of FramebufferNativeWindow to keep
legacy EGL implementations happy.  Confirmed EGL
implementations that need this include but are
not limited to:

Set BOARD_EGL_NEEDS_FNW to use

Tegra2/3 ICS EGL
Mali400 ICS EGL (Allwinner A10)
Mali400 Jellybean (4.1) EGL (Samsung Exynos4)
Adreno Jellybean (4.1) EGL (legacy qcom devices using PMEM)

Original implementation by OndraOrg of XDA:
http://forum.xda-developers.com/showpost.php?p=34469675&postcount=19

Change-Id: If7c455035a002f272fa1a8af1cfcc60eb7ade894

Conflicts:

	services/surfaceflinger/Android.mk
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