[Blink>Media] Add Chrome feature for disabling autoplay unmuted in WebAPK

chrome/common/chrome_features.cc

 // Copyright 2016 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.
 
 #include "chrome/common/chrome_features.h"
 
 #include "extensions/features/features.h"
 #include "ppapi/features/features.h"
 
 namespace features {
 
 // All features in alphabetical order.
 
+#if defined(OS_ANDROID)
+const base::Feature kAllowAutoplayUnmutedInWebappManifestScope{
+    "AllowAutoplayUnmutedInWebappManifestScope",
+    base::FEATURE_ENABLED_BY_DEFAULT};
+#endif  // defined(OS_ANDROID)
+
 #if defined(OS_MACOSX)
 // Enables Javascript execution via AppleScript.
 const base::Feature kAppleScriptExecuteJavaScript{
     "AppleScriptExecuteJavaScript", base::FEATURE_ENABLED_BY_DEFAULT};
 #endif  // defined(OS_MACOSX)
 
 #if defined(OS_CHROMEOS)
 // Whether to handle low memory kill of ARC apps by Chrome.
 const base::Feature kArcMemoryManagement{
     "ArcMemoryManagement", base::FEATURE_ENABLED_BY_DEFAULT};
@@ skipping 250 matching lines @@
 // Enables or disables emoji, handwriting and voice input on opt-in IME menu.
 const base::Feature kEHVInputOnImeMenu{"EmojiHandwritingVoiceInput",
                                        base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Enables or disables flash component updates on Chrome OS.
 const base::Feature kCrosCompUpdates{"CrosCompUpdates",
                                      base::FEATURE_ENABLED_BY_DEFAULT};
 #endif  // defined(OS_CHROMEOS)
 
 }  // namespace features