Remove requirement that mojo::Environment be instantiated.

mojo/public/cpp/bindings/tests/bindings_perftest.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 "mojo/public/cpp/bindings/binding.h"
 #include "mojo/public/cpp/test_support/test_support.h"
 #include "mojo/public/cpp/utility/run_loop.h"
 #include "mojo/public/interfaces/bindings/tests/ping_service.mojom.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 65 matching lines @@
     binding.Bind(GetProxy(&service));
   }
 
   PingServiceImpl impl;
   test::PingServicePtr service;
   Binding<test::PingService> binding;
 };
 
 class MojoBindingsPerftest : public testing::Test {
  protected:
-  Environment env_;
   RunLoop run_loop_;
 };
 
 TEST_F(MojoBindingsPerftest, InProcessPingPong) {
   test::PingServicePtr service;
   PingServiceImpl impl;
   Binding<test::PingService> binding(&impl, GetProxy(&service));
   PingPongTest test(service.Pass());
 
   {
@@ skipping 20 matching lines @@
         "InProcessPingPong", "1000_Inactive",
         kIterations / MojoTicksToSeconds(end_time - start_time),
         "pings/second");
 
     delete[] inactive_services;
   }
 }
 
 }  // namespace
 }  // namespace mojo