telemetry: support old builds that still use disable-gesture-requirement-for-media-playback flag.

tools/perf/benchmarks/media.py

Index: tools/perf/benchmarks/media.py
diff --git a/tools/perf/benchmarks/media.py b/tools/perf/benchmarks/media.py
index ddccefb6b1dc55ee1ed44ed7b47a4ae72f4cfc8d..74fd0ae19363f9c102784bdea02640dcee04cf7b 100644
--- a/tools/perf/benchmarks/media.py
+++ b/tools/perf/benchmarks/media.py
@@ -156,7 +156,12 @@ class MediaAndroidToughVideoCasesTBMv2(_MediaTBMv2Benchmark):
     # By default, Chrome on Android does not allow autoplay
     # of media: it requires a user gesture event to start a video.
     # The following option works around that.
-    options.AppendExtraBrowserArgs(['--ignore-autoplay-restrictions'])
+    # Note that both of these flags should be used until every build from
+    # ToT to Stable switches over to one flag or another. This is to support
+    # reference builds.
+    options.AppendExtraBrowserArgs(
+        ['--ignore-autoplay-restrictions',
+         '--disable-gesture-requirement-for-media-playback'])
 
 
 # This isn't running anywhere. See crbug/709161.