Mojo: Cancel WaitingCallbacks when their HandleWrappers are closed.

mojo/bindings/js/handle.cc

Index: mojo/bindings/js/handle.cc
diff --git a/mojo/bindings/js/handle.cc b/mojo/bindings/js/handle.cc
index e1d0fb04b60c063466536c04f48502c7b1423179..1c7dee608e149514e01d920f80c0183e6d60eb50 100644
--- a/mojo/bindings/js/handle.cc
+++ b/mojo/bindings/js/handle.cc
@@ -13,6 +13,24 @@ HandleWrapper::HandleWrapper(MojoHandle handle)
 }
 
 HandleWrapper::~HandleWrapper() {
+  NotifyCloseObservers();
+}
+
+void HandleWrapper::Close() {
+  NotifyCloseObservers();
+  handle_.reset();
+}
+
+void HandleWrapper::AddCloseObserver(CloseObserver* observer) {
+  close_observers_.AddObserver(observer);
+}
+
+void HandleWrapper::RemoveCloseObserver(CloseObserver* observer) {
+  close_observers_.RemoveObserver(observer);
+}
+
+void HandleWrapper::NotifyCloseObservers() {
+  FOR_EACH_OBSERVER(CloseObserver, close_observers_, OnHandleClosed());

[sky, 2014/09/03 15:47:04]

Should we only notify the observers if the handle is valid when we get here? For
example, if someone explicitly invokes Close() and then deletes the
HandleWrapper do they really want two observer notifications?

[Sam McNally, 2014/09/08 04:31:52]

Done.

 }
 
 v8::Handle<v8::Value> Converter<mojo::Handle>::ToV8(v8::Isolate* isolate,