multibuffer field trial

media/base/media_switches.cc

Index: media/base/media_switches.cc
diff --git a/media/base/media_switches.cc b/media/base/media_switches.cc
index bc5d67fb921fd52a748f3d1f22780bb3e4ded5c3..a69808aa5744dac69bb5531d0706bb82fa37e44f 100644
--- a/media/base/media_switches.cc
+++ b/media/base/media_switches.cc
@@ -129,7 +129,12 @@ const char kVideoUnderflowThresholdMs[] = "video-underflow-threshold-ms";
 const char kDisableRTCSmoothnessAlgorithm[] =
     "disable-rtc-smoothness-algorithm";
 
+}  // namespace switches
+
+namespace media {
+
 // Use shared block-based buffering for media.
-const char kUseNewMediaCache[] = "use-new-media-cache";
+const base::Feature kUseNewMediaCache{"use-new-media-cache",
+                                      base::FEATURE_DISABLED_BY_DEFAULT};
 
-}  // namespace switches
+}  // namespace media