Adds a way to determine id of content handler that created app

mojo/shell/capability_filter_unittest.cc

 // Copyright 2015 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 "base/at_exit.h"
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
 #include "base/stl_util.h"
@@ skipping 334 matching lines @@
     // because we don't allow the test application to connect to test:validator.
     // Adding it to the CapabilityFilter would interfere with the test.
     ServiceProviderPtr exposed_services;
     (new ServiceProviderImpl(GetProxy(&exposed_services)))->
         AddService<Validator>(validator_);
     URLRequestPtr request(URLRequest::New());
     request->url = String::From(url);
     application_manager_->ConnectToApplication(
         nullptr, request.Pass(), std::string(), GURL(), GetProxy(&services),
         exposed_services.Pass(), filter,
-        base::MessageLoop::QuitWhenIdleClosure());
+        base::MessageLoop::QuitWhenIdleClosure(), EmptyConnectCallback());
   }
 
   void InitValidator(const std::set<std::string>& expectations) {
     validator_ = new ConnectionValidator(expectations, &loop_);
     application_manager()->SetLoaderForURL(make_scoped_ptr(validator_),
                                            GURL("test:validator"));
   }
 
   template <class T>
   void CreateLoader(const std::string& url) {
@@ skipping 179 matching lines @@
   RunTest();
 }
 
 TEST_F(CapabilityFilter_WildcardsTest, ContentHandler) {
   RunContentHandlerTest();
 }
 
 }  // namespace
 }  // namespace shell
 }  // namespace mojo