[geary/wip/strict-async-out-param-0.12] Update WebKitGTK bindings metadata from vala 0.42.5

[Michael Gratton <mjog src gnome org>]

commit 1e8e46f5be86281decb3cf9b976967ebd2b13879
Author: Michael Gratton <mike vee net>
Date:   Wed Feb 6 17:18:16 2019 +1100

    Update WebKitGTK bindings metadata from vala 0.42.5
    
    Fixes vapigen error with that version.

 bindings/metadata/WebKit2-4.0.metadata             | 13 +++++++------
 bindings/metadata/WebKit2WebExtension-4.0.metadata | 12 ++++++++++--
 2 files changed, 17 insertions(+), 8 deletions(-)
---
diff --git a/bindings/metadata/WebKit2-4.0.metadata b/bindings/metadata/WebKit2-4.0.metadata
index 3e3044ff..d650ba97 100644
--- a/bindings/metadata/WebKit2-4.0.metadata
+++ b/bindings/metadata/WebKit2-4.0.metadata
@@ -1,15 +1,16 @@
-
-JavascriptResult
-    .get_global_context nullable=false unowned=true
-    .get_value nullable=false unowned=true
-
 //Forward upstream
 Download
   .failed#signal.error type="WebKit.DownloadError"
+JavascriptResult
+  .get_global_context type="unowned JS.GlobalContext" skip=false
+  .get_value type="unowned JS.Value" skip=false
 PrintOperation
   .failed#signal.error type="WebKit.PrintError"
 WebResource
   .failed#signal.error type="GLib.Error"
 WebView
+  .get_javascript_global_context type="unowned JS.GlobalContext" skip=false
   .load_failed#signal.error type="GLib.Error"
-  .show_option_menu#signal skip
+  .show_option_menu#signal name="on_show_option_menu"
+
+*.ref unowned
diff --git a/bindings/metadata/WebKit2WebExtension-4.0.metadata 
b/bindings/metadata/WebKit2WebExtension-4.0.metadata
index c496dba4..5037d48f 100644
--- a/bindings/metadata/WebKit2WebExtension-4.0.metadata
+++ b/bindings/metadata/WebKit2WebExtension-4.0.metadata
@@ -4,6 +4,14 @@ DOMEventTarget.add_event_listener skip
 _ContextMenu skip
 _ContextMenuItem skip
 
-Frame.get_javascript_* nullable=false unowned=true
-
+DOMEventTarget.add_event_listener_with_closure abstract vfunc_name="add_event_listener"
 DOMEventTarget.add_event_listener_with_closure.handler type="owned WebKit.DOM.EventTargetFunc"
+DOMEventTarget.remove_event_listener_with_closure abstract vfunc_name="remove_event_listener"
+DOMEventTarget.remove_event_listener_with_closure.handler type="owned WebKit.DOM.EventTargetFunc"
+
+Frame
+  .get_javascript_context_for_script_world type="unowned JS.GlobalContext" skip=false
+  .get_javascript_global_context type="unowned JS.GlobalContext" skip=false
+
+URIRequest.get_http_headers unowned
+URIResponse.get_http_headers unowned