hwc: cache layers on framebuffer

In the cases where all the layers that are marked as HWC_FRAMEBUFFER did not
change, we can mark them as HWC_OVERLAY since their contents are already on the
framebuffer and do not need any additional processing.

This optimization shows power improvement for video playback.

Bug: 7623741
Change-Id: Ia178a926e6f56a3ec9291250a22a66f212c30b14
Signed-off-by: Iliyan Malchev <malchev@google.com>
hwc/overlay: Dynamic pipe tracking.

Remove state based pipe handling and make pipes tracked dynamically.
Add the configStart, configDone, nextPipe availablePipes APIs.
Remove setState API.

-configStart marks all pipes available.
-configDone garbage-collects unused pipe objects.
-nextPipe returns the index of next available pipe and create a corresponding
pipe object if not present
-availablePipes returns total of "unallocated" pipes. (Pipes could be allocated
but unused)

Changes in hwc adapt to the new overlay APIs.
Compile out MDP comp.
Remove unused files in overlay and hwc.
Update licenses.

Conflicts:

	libhwcomposer/hwc.cpp
	libhwcomposer/hwc_utils.cpp

Bug: 7626586
Change-Id: Id8e56901d34e5dc0fd088260d05e3e46f68ff090
Signed-off-by: Saurabh Shah <saurshah@codeaurora.org>
Signed-off-by: Iliyan Malchev <malchev@google.com>
display: Add support for flip operation in MDP comp

This change adds support for flip operation during MDP composition. This
enables frames to get MDP composited during 270 degree orientation too (with
pre rotation doing 90 degree rotation) or even with layers with just h flip or
v flip.

Bug: 7435860
Change-Id: I7fd18226d8337b2cd9341d709c2bd030eff881f7
Signed-off-by: Iliyan Malchev <malchev@google.com>
libhwcomposer: Add support for 4 layer MDP Comp

This change extends MDP composition to support
upto 4 layers by making border fill as base pipe and
using all MDP h/w pipes in overlay mode.

Conflicts:

	libhwcomposer/hwc.cpp
	libhwcomposer/hwc_utils.cpp
	libhwcomposer/hwc_utils.h

Bug: 7626586
Change-Id: I01a0e53ddfbcf3ed46734f6f3bb0ef7d912ceac6
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Iliyan Malchev <malchev@google.com>