Add a feature flag for enabling subscription restrictions

content/public/common/content_features.cc

 // 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.
 
 #include "build/build_config.h"
 #include "content/public/common/content_features.h"
 
 namespace features {
 
 // All features in alphabetical order.
@@ skipping 68 matching lines @@
 
 // An experimental User Agent Intervention on WebFonts loading.
 const base::Feature kWebFontsIntervention{"WebFontsIntervention",
                                           base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Makes WebRTC use ECDSA certs by default (i.e., when no cert type was
 // specified in JS).
 const base::Feature kWebRtcEcdsaDefault {"WebRTC-EnableWebRtcEcdsa",
                                          base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Enables support for restricting push messaging subscriptions to a specific

[Michael van Ouwerkerk, 2016/04/15 16:13:41]

I would expect that the WebPushProtocol feature enables use of the Web Push
Protocol, but this description is quite different. Is this a typo or do we need
to have a chat?

+// application server, which is an alternative authentication mechanism for push
+// services required for the Web Push Protocol. See http://crbug.com/601825
+const base::Feature kWebPushProtocol{
+    "WebPushProtocol", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Controls whether the WebUSB API is enabled:
 // https://wicg.github.io/webusb
 const base::Feature kWebUsb{"WebUSB", base::FEATURE_ENABLED_BY_DEFAULT};
 
 #if defined(OS_ANDROID)
 // Use IME's own thread instead of using main UI thread. It also means that
 // we will not use replica editor and do a round trip to renderer to synchronize
 // with Blink data.
 const base::Feature kImeThread{"ImeThread", base::FEATURE_DISABLED_BY_DEFAULT};
 
 // FeatureList definition for the Seccomp field trial.
 const base::Feature kSeccompSandboxAndroid{"SeccompSandboxAndroid",
                                            base::FEATURE_DISABLED_BY_DEFAULT};
 #endif
 
 }  // namespace features