Merge "DO NOT MERGE: Decoder: Conceal picture only if valid picture buffer is...

Merge "DO NOT MERGE: Decoder: Conceal picture only if valid picture buffer is obtained." into mnc-dev am: dc939697  -s ours am: 24cb0c18  -s ours am: da8110e0  -s ours am: ff04804d  -s ours am: 80e0518c  -s ours am: ac52a6e6  -s ours am: 44d01f90  -s ours am: 9772d551  -s ours am: cb1c308c  -s ours am: d4b2adb2  -s ours
am: 523f1ad2  -s ours

Change-Id: I1b2dc9d0e0b302d97c0bb43659f10a9e67b587a2