Reintroduce plumbing for user gesture into permission system.

chrome/browser/push_messaging/push_messaging_service_impl.cc

Index: chrome/browser/push_messaging/push_messaging_service_impl.cc
diff --git a/chrome/browser/push_messaging/push_messaging_service_impl.cc b/chrome/browser/push_messaging/push_messaging_service_impl.cc
index 5e5314b9ecee9725cb6d9e5fd1341dc255b60d09..eadfbffa22d3b070dbe48d046752c2ce7bd996af 100644
--- a/chrome/browser/push_messaging/push_messaging_service_impl.cc
+++ b/chrome/browser/push_messaging/push_messaging_service_impl.cc
@@ -398,7 +398,7 @@ void PushMessagingServiceImpl::SubscribeFromDocument(
   // Push does not allow permission requests from iframes.
   profile_->GetPermissionManager()->RequestPermission(
       content::PermissionType::PUSH_MESSAGING, web_contents->GetMainFrame(),
-      requesting_origin,
+      requesting_origin, true /* user_gesture */,
       base::Bind(&PushMessagingServiceImpl::DidRequestPermission,
                  weak_factory_.GetWeakPtr(), app_identifier, options,
                  callback));