Add stats for average QP per frame for VP8 (for received video streams).

webrtc/modules/video_coding/utility/qp_parser.cc

Index: webrtc/modules/video_coding/utility/qp_parser.cc
diff --git a/webrtc/modules/audio_coding/codecs/isac/locked_bandwidth_info.cc b/webrtc/modules/video_coding/utility/qp_parser.cc
similarity index 50%
copy from webrtc/modules/audio_coding/codecs/isac/locked_bandwidth_info.cc
copy to webrtc/modules/video_coding/utility/qp_parser.cc
index 78b415c4c950224a459759cb681b8f04f807b6b4..09728f98caaad1687cdb662243c26f55c4dc04a7 100644
--- a/webrtc/modules/audio_coding/codecs/isac/locked_bandwidth_info.cc
+++ b/webrtc/modules/video_coding/utility/qp_parser.cc
@@ -8,15 +8,21 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "webrtc/modules/audio_coding/codecs/isac/locked_bandwidth_info.h"
+#include "webrtc/modules/video_coding/utility/include/qp_parser.h"
+
+#include "webrtc/modules/video_coding/utility/include/vp8_header_parser.h"
 
 namespace webrtc {
 
-LockedIsacBandwidthInfo::LockedIsacBandwidthInfo()
-      : lock_(CriticalSectionWrapper::CreateCriticalSection()) {
-  bwinfo_.in_use = 0;
+bool QpParser::GetQp(const uint8_t* encoded_frame,
+                     size_t length,
+                     VideoCodecType codec_type,
+                     int* qp) {
+  if (codec_type == kVideoCodecVP8) {
+    // QP range: [0, 127].
+    return vp8::GetQp(encoded_frame, length, qp);
+  }
+  return false;
 }
 
-LockedIsacBandwidthInfo::~LockedIsacBandwidthInfo() = default;
-
 }  // namespace webrtc