remoting: Cleanup class/struct fwd declarations

remoting/test/chromoting_test_fixture.h

 // 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.
 
 #ifndef REMOTING_TEST_CHROMOTING_TEST_FIXTURE_H_
 #define REMOTING_TEST_CHROMOTING_TEST_FIXTURE_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/threading/thread_checker.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-namespace base {
-class RunLoop;
-class Timer;
-}
-
 namespace remoting {
 namespace test {
 
 class ConnectionTimeObserver;
 class TestChromotingClient;
-struct HostInfo;
 
 // Provides chromoting connection capabilities for tests to use. Performance
 // metrics of the established connection are readily available to calculate
 // through the ConnectionTimeObserver.
 class ChromotingTestFixture
     : public testing::Test {
  public:
   ChromotingTestFixture();
   ~ChromotingTestFixture() override;
 
@@ skipping 23 matching lines @@
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromotingTestFixture);
 };
 
 }  // namespace test
 }  // namespace remoting
 
 #endif  // REMOTING_TEST_CHROMOTING_TEST_FIXTURE_H_