Upgrade Sky's use of the JS bindings

sky/framework/shell.sky

-<import src="/gen/mojo/public/sky/core.sky" as="core" />
 <import src="/gen/mojo/public/sky/connection.sky" as="connection" />
 <script>
-function wrapHandle(handle, service, client) {
-  return connection.bindProxyHandle(handle, service.client, service);
-}
-
 function connectToService(url, service, client) {
   var handle = internals.connectToService(url, service.name);
-  return wrapHandle(handle, service, client);
+  return connection.bindHandleToProxy(handle, service);
 }
 
 module.exports = {
   connectToService: connectToService,
-  wrapHandle: wrapHandle,
 };
 </script>