Add a feature flag for enabling subscription restrictions

content/public/common/content_features.cc

Index: content/public/common/content_features.cc
diff --git a/content/public/common/content_features.cc b/content/public/common/content_features.cc
index d904a83099ec4cb8acab4a74f3ffd29df0665bd0..e13dcaf2867b9779e03e11f922de57a18cc6ccd0 100644
--- a/content/public/common/content_features.cc
+++ b/content/public/common/content_features.cc
@@ -86,6 +86,12 @@ const base::Feature kWebFontsIntervention{"WebFontsIntervention",
 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};