Remove requirement that mojo::Environment be instantiated.

mojo/public/cpp/environment/tests/async_waiter_unittest.cc

 // Copyright 2014 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/callback.h"
 #include "mojo/public/cpp/environment/async_waiter.h"
 #include "mojo/public/cpp/test_support/test_utils.h"
 #include "mojo/public/cpp/utility/run_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 31 matching lines @@
 
  private:
   TestAsyncWaitCallback* callback_;
 };
 
 class AsyncWaiterTest : public testing::Test {
  public:
   AsyncWaiterTest() {}
 
  private:
-  Environment environment_;
   RunLoop run_loop_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(AsyncWaiterTest);
 };
 
 // Verifies AsyncWaitCallback is notified when pipe is ready.
 TEST_F(AsyncWaiterTest, CallbackNotified) {
   TestAsyncWaitCallback callback;
   MessagePipe test_pipe;
   EXPECT_TRUE(test::WriteTextMessage(test_pipe.handle1.get(), std::string()));
@@ skipping 35 matching lines @@
   {
     AsyncWaiter waiter(test_pipe.handle0.get(), MOJO_HANDLE_SIGNAL_READABLE,
                        ManualCallback(&callback));
   }
   RunLoop::current()->Run();
   EXPECT_EQ(0, callback.result_count());
 }
 
 }  // namespace
 }  // namespace mojo