Make BaseView et al. take an ApplicationConnector instead of an ApplicationImpl.

mojo/public/cpp/application/lib/connect.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/public/cpp/application/connect.h"
 
 #include "mojo/public/interfaces/application/shell.mojom.h"
 
 namespace mojo {
 
 InterfaceHandle<ApplicationConnector> CreateApplicationConnector(Shell* shell) {
   InterfaceHandle<ApplicationConnector> application_connector;
   shell->CreateApplicationConnector(GetProxy(&application_connector));
   return application_connector;
 }
 
+InterfaceHandle<ApplicationConnector> DuplicateApplicationConnector(
+    ApplicationConnector* application_connector) {
+  InterfaceHandle<ApplicationConnector> new_application_connector;
+  application_connector->Duplicate(GetProxy(&new_application_connector));
+  return new_application_connector;
+}
+
 }  // namespace mojo