SurfaceFlinger: Add NULL check for buffer handling

Add buffer handling NULL check in dequeueBuffer and
verify whether the output data from binder is not NULL
in queueBuffer and connect api's to avoid SF crash

CRs-Fixed: 573088
CRs-Fixed: 572315

Change-Id: I41cebbc0cbcbbb0fd5ecb38db7ec7b0c91cdffe9
libs/ui: Fix crash issue because of null pointer access

- handle NULL check is required while flatten GraphicsBuffer

CRs-fixed: 579102

Change-Id: I292b4b25dc1f5320378cc9e4affbad326e1fdaed
SurfaceFlinger: Change to support framebuffer flip for 2D blitters

- Surfaceflinger does not flip framebuffers when there are
  no layers marked for HWC_FRAMEBUFFER
- This change checks for the HWC_BLIT flag and will request a flip
  to a new FB_TARGET buffer even if there are no FRAMEBUFFER layers

Change-Id: Ib045e562481c6447d2064fc9693057652b417479
surfaceflinger: Apply bugfixes to the correct hwc code paths

Changes I2deaf2ed101e8ea76708862a6bb67751b6078794 and
I1cb44389a05c9ec049d7f0d39c288feccb11a91c, both meant to deal
with corner-case layer states, were mistakenly merged into
the pre-1.0-hwc code paths. Move them to their intended locations

Change-Id: Idd6b3513cc36dda21b552eee97f9ea91793df18f
SurfaceFlinger: Enable Vsync trace for SF Composition

Enable traces to show s/w vsync which is used for composition
by surfaceflinger, this helps in identifying the start of
composition cycle in systrace

Change-Id: Id892ca03bacd9f0cfe5ca2c3f8bb5aa892b37231
frameworks/native: Add support for Secure Display

- Add secure UI layers to primary and remove other layers from
  internal and external list for Secure Display usecase.
- Dont let secure UI layers to be captured on screen

Change-Id: Iebdad5c56247308604ee90928f6d6460a1f69279
SF: Block gpu rendering for virtual display widevine level3

In MPD3 we are using the widevine level3 for secure content
display. And this should applicable only for primary display
not for screen shot or screen recording.

CRs-Fixed: 595469
Change-Id: I99be2d81287ab746d5c4a2375c3106c59e61a8fc