[Media] Added feature flag for new remote playback pipeline

chrome/browser/flag_descriptions.cc

Index: chrome/browser/flag_descriptions.cc
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 6127251646572b93a8d26b29bf6dfc34200a833f..1579a892b9b66b575a036a5faca6f4cbec409172 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2581,6 +2581,15 @@ const char kBackgroundVideoTrackOptimizationDescription[] =
     "Disable video tracks when the video is played in the background to "
     "optimize performance.";
 
+//  New remote playback pipeline experiment strings.
+
+const char kNewRemotePlaybackPipelineName[] =
+    "Enable the new remote playback pipeline.";
+
+const char kNewRemotePlaybackPipelineDescription[] =
+    "Enable the new pipeline for playing media element remotely via "
+    "RemotePlayback API or native controls.";
+
 //  Video fullscreen with orientation lock experiment strings.
 
 const char kVideoFullscreenOrientationLockName[] =