libmix: fix the buffer status messy issue

BZ: 20262 18785

when getting new sps/pps, but the resolution is not
changed, we won't sent out format_changed, it is a
workaround here
Signed-off-by: Weian Chen <weian.chen@intel.com>

Change-Id: I670b329df58c5fa494a9e5bb69baee92798dbc62
Reviewed-on: http://android.intel.com:8080/33841
Reviewed-by: Wang, Yi A <yi.a.wang@intel.com>
Reviewed-by: Ding, Haitao <haitao.ding@intel.com>
Tested-by: Ding, Haitao <haitao.ding@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>
diff --git a/videodecoder/VideoDecoderAVC.cpp b/videodecoder/VideoDecoderAVC.cpp
index 6613935..dbb13d4 100644
--- a/videodecoder/VideoDecoderAVC.cpp
+++ b/videodecoder/VideoDecoderAVC.cpp
@@ -673,6 +673,7 @@
     if (width == mVideoFormatInfo.width &&
         height == mVideoFormatInfo.height) {
         ITRACE("New video sequence with the same resolution.");
+        mSizeChanged = false;
     } else {
         WTRACE("Video size changed from %d x %d to %d x %d.", width, height,
                 mVideoFormatInfo.width, mVideoFormatInfo.height);