Fix issue with parsing of incorrect (empty) Stap-A H264 NAL units.

webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc b/webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc
index 64a2a94b7eb8078328c343277b12b653cdf19749..24ebe769de08f2f7580dc4aaff5c7e830b765fcc 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_format_h264.cc
@@ -403,6 +403,11 @@ bool RtpDepacketizerH264::ProcessStapAOrSingleNalu(
     // End offset is actually start offset for next unit, excluding length field
     // so remove that from this units length.
     size_t end_offset = nalu_start_offsets[i + 1] - kLengthFieldSize;
+    if (end_offset - start_offset < H264::kNaluTypeSize) {
+      LOG(LS_ERROR) << "STAP-A packet too short";
+      return false;
+    }
+
     nal_type = payload_data[start_offset] & kTypeMask;
     start_offset += H264::kNaluTypeSize;