Mojo: Cancel WaitingCallbacks when their HandleWrappers are closed.

mojo/bindings/js/support.cc

Index: mojo/bindings/js/support.cc
diff --git a/mojo/bindings/js/support.cc b/mojo/bindings/js/support.cc
index dc97865cca79ce32cb8c4000f8c072e5e4b8c574..1c82f17c0876caa87bdddfe9be855c680a6d4e3e 100644
--- a/mojo/bindings/js/support.cc
+++ b/mojo/bindings/js/support.cc
@@ -21,7 +21,8 @@ namespace js {
 
 namespace {
 
-WaitingCallback* AsyncWait(const gin::Arguments& args, mojo::Handle handle,
+WaitingCallback* AsyncWait(const gin::Arguments& args,
+                           gin::Handle<gin::HandleWrapper> handle,
                            MojoHandleSignals signals,
                            v8::Handle<v8::Function> callback) {
   return WaitingCallback::Create(args.isolate(), callback, handle, signals)