Enable MidiManagerWinrt by default on Windows 10

media/midi/midi_switches.h

Index: media/midi/midi_switches.h
diff --git a/media/midi/midi_switches.h b/media/midi/midi_switches.h
index 923533f2ae595e9d9614e318bab5cd43fbba83f4..46e010a933b5dd69e983f7c63d5aa57c84d2ef13 100644
--- a/media/midi/midi_switches.h
+++ b/media/midi/midi_switches.h
@@ -17,18 +17,10 @@ namespace switches {
 MIDI_EXPORT extern const char kUseAndroidMidiApi[];
 #endif
 
-}  // namespace switches
-
-namespace media {
-namespace midi {
-namespace features {
-
 #if defined(OS_WIN)
-MIDI_EXPORT extern const base::Feature kMidiManagerWinrt;
+MIDI_EXPORT extern const char kDisableWinrtMidiApi[];
 #endif
 
-}  // namespace features
-}  // namespace midi
-}  // namespace media
+}  // namespace switches
 
 #endif  // MEDIA_MIDI_MIDI_SWITCHES_H_