libvideorender: CB1 fix crash on weston [1/1]

PD#SWPL-198922

Problem:
crash happened on handleFrameTime.
renderBuffer of WaylandBuffer is null.if bufferRelease
takes long time,but prepare buffer at this time. after
bufferRelease set renderBuffer to null

Solution:
1.using mutex to protect renderBuffer
2.constructWlBuffer renderBuffer again if detected
renderBuffer is null

Verify:
ap222

Change-Id: If92f16e13f190b58977a80e56151658b324ff90a
Signed-off-by: fei.deng <fei.deng@amlogic.com>
2 files changed