[epiphany] window: Add a comment

[Michael Catanzaro <mcatanzaro src gnome org>]

commit a8a9e257676040ecb272707ad2333072182852d0
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sat Jan 6 18:59:01 2018 -0600

    window: Add a comment
    
    I was confused how it was possible to complete the policy decision
    asynchronously if we do not ref it anywhere. We do, it's just hidden.

 src/ephy-window.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/ephy-window.c b/src/ephy-window.c
index a700fab..1b9897b 100644
--- a/src/ephy-window.c
+++ b/src/ephy-window.c
@@ -2090,6 +2090,7 @@ decide_policy_cb (WebKitWebView           *web_view,
     service = ephy_embed_shell_get_global_gsb_service (ephy_embed_shell_get_default ());
     ephy_gsb_service_verify_url (service, request_uri,
                                  (GAsyncReadyCallback)verify_url_cb,
+                                 /* Note: this refs the policy decision, so we can complete it 
asynchronously. */
                                  verify_url_async_data_new (window, web_view,
                                                             decision, decision_type,
                                                             request_uri));