Remove MediaDevices runtime flag (status=stable)

third_party/WebKit/Source/modules/mediastream/MediaDevices.idl

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // The spec for MediaDevices is in two parts:
 // http://w3c.github.io/mediacapture-main/#mediadevices
 // http://w3c.github.io/mediacapture-main/#mediadevices-interface-extensions
 
 [
     ActiveScriptWrappable,
     DependentLifetime,
-    ConstructorCallWith=ExecutionContext,
-    RuntimeEnabled=MediaDevices
+    ConstructorCallWith=ExecutionContext
 ]
 interface MediaDevices : EventTarget {
     [CallWith=ScriptState, MeasureAs=MediaDevicesEnumerateDevices] Promise<sequence<MediaDeviceInfo>> enumerateDevices();
     [RuntimeEnabled=MediaConstraints] MediaTrackSupportedConstraints getSupportedConstraints();
     [RuntimeEnabled=GetUserMedia,
      CallWith=ScriptState,
      RaisesException,
      MeasureAs=GetUserMediaPromise
     ] Promise<MediaStream> getUserMedia(MediaStreamConstraints options);
     [RuntimeEnabled=OnDeviceChange] attribute EventHandler ondevicechange;
 };