[Media controls] Add rotate-to-fullscreen gesture behind flag

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 571974cd77a5f13cc5d4085dac1d5f3cb2210c89..72b2b7553a0c90c6b53a9081daec623e9f994213 100644
--- a/media/base/media_switches.cc
+++ b/media/base/media_switches.cc
@@ -213,6 +213,10 @@ const base::Feature kExternalClearKeyForTesting{
 const base::Feature kVideoFullscreenOrientationLock{
     "VideoFullscreenOrientationLock", base::FEATURE_ENABLED_BY_DEFAULT};
 
+// Enter/exit fullscreen when device is rotated to/from the video orientation.
+const base::Feature kVideoRotateToFullscreen{"VideoRotateToFullscreen",
+                                             base::FEATURE_DISABLED_BY_DEFAULT};
+
 // An experimental feature to enable persistent-license type support in MediaDrm
 // when using Encrypted Media Extensions (EME) API.
 // TODO(xhwang): Remove this after feature launch. See http://crbug.com/493521