Add a simple one shot and repeating timer API for Mojo.js.

mojo/apps/js/bindings/threading.cc

Index: mojo/apps/js/bindings/threading.cc
diff --git a/mojo/apps/js/bindings/threading.cc b/mojo/apps/js/bindings/threading.cc
index 86d0d789faa3384ec8fda415a4d8479e2ee9f8d4..4b10bff0d170836002ef0501ee5561b6ad58f958 100644
--- a/mojo/apps/js/bindings/threading.cc
+++ b/mojo/apps/js/bindings/threading.cc
@@ -24,7 +24,7 @@ gin::WrapperInfo g_wrapper_info = { gin::kEmbedderNativeGin };
 
 const char Threading::kModuleName[] = "mojo/apps/js/bindings/threading";
 
-v8::Local<v8::ObjectTemplate> Threading::GetTemplate(v8::Isolate* isolate) {
+v8::Local<v8::Value> Threading::GetModule(v8::Isolate* isolate) {
   gin::PerIsolateData* data = gin::PerIsolateData::From(isolate);
   v8::Local<v8::ObjectTemplate> templ = data->GetObjectTemplate(
       &g_wrapper_info);
@@ -37,7 +37,7 @@ v8::Local<v8::ObjectTemplate> Threading::GetTemplate(v8::Isolate* isolate) {
     data->SetObjectTemplate(&g_wrapper_info, templ);
   }
 
-  return templ;
+  return templ->NewInstance();
 }
 
 Threading::Threading() {