Add VP9 to chrome_webrtc_perf_browsertest.cc.

chrome/browser/media/webrtc_browsertest_perf.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_MEDIA_WEBRTC_BROWSERTEST_PERF_H_
 #define CHROME_BROWSER_MEDIA_WEBRTC_BROWSERTEST_PERF_H_
 
 #include <string>
 
 namespace base {
 class DictionaryValue;
 }
 
 namespace test {
 
 // These functions takes parsed data (on one peer connection) from the
 // peerConnectionDataStore object that is backing webrtc-internals and prints
 // metrics they consider interesting using testing/perf/perf_test.h primitives.
 // The idea is to put as many webrtc-related metrics as possible into the
 // dashboard and thereby track it for regressions.
 //
 // These functions expect to run under googletest and will use EXPECT_ and
 // ASSERT_ macros to signal failure. They take as argument one peer connection's
 // stats data and a |modifier| to append to each result bucket. For instance, if
 // the modifier is '_oneway', the rtt stat will be logged as goog_rtt in
 // the video_tx_oneway bucket.
+// If |video_codec| is a non-empty string, the codec name is appended last for
+// video metrics, e.g. 'video_tx_oneway_VP9'.
 void PrintBweForVideoMetrics(const base::DictionaryValue& pc_dict,
-                             const std::string& modifier);
+                             const std::string& modifier,
+                             const std::string& video_codec);
 void PrintMetricsForAllStreams(const base::DictionaryValue& pc_dict,
-                               const std::string& modifier);
+                               const std::string& modifier,
+                               const std::string& video_codec);
 
 }  // namespace test
 
 #endif  // CHROME_BROWSER_MEDIA_WEBRTC_BROWSERTEST_PERF_H_