set the picture flag to be invalid frame if the ref frame is invalid

fixes #1189

Signed-off-by: XinfengZhang <carl.zhang@intel.com>
(cherry picked from commit 8c20821942d0025366322a2ffa6deb79150cf56e)
Change-Id: I404aa8db27126846bfc0c6728546ca38c58f1b47
1 file changed