Merge "MediaMetadataRetriever: Fix null pointer exception"

                || thumbPixels * 6 >= maxPixels) {

            frameMemory = retriever->getImageAtIndex(

                    index, colorFormat, false /*metaOnly*/, true /*thumbnail*/);

            if (frameMemory != 0) {

                // TODO: Using unsecurePointer() has some associated security pitfalls

                //       (see declaration for details).

                //       Either document why it is safe in this case or address the

                //       issue (e.g. by copying).

                videoFrame = static_cast<VideoFrame *>(frameMemory->unsecurePointer());

            }

            if (thumbPixels > maxPixels) {

                int downscale = ceil(sqrt(thumbPixels / (float)maxPixels));