Move scoped_test_dir.* and test_io_thread.* from edk/test to edk/system/test.

mojo/edk/system/test/test_io_thread.h

 // Copyright 2013 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 MOJO_EDK_TEST_TEST_IO_THREAD_H_
-#define MOJO_EDK_TEST_TEST_IO_THREAD_H_
+#ifndef MOJO_EDK_SYSTEM_TEST_TEST_IO_THREAD_H_
+#define MOJO_EDK_SYSTEM_TEST_TEST_IO_THREAD_H_
 
 #include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
 #include "base/task_runner.h"
 #include "base/threading/thread.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace mojo {
+namespace system {
 namespace test {
 
 // Class to help create/run threads with I/O |MessageLoop|s in tests.
 class TestIOThread {
  public:
   enum class StartMode { AUTO, MANUAL };
   explicit TestIOThread(StartMode start_mode);
   // Stops the I/O thread if necessary.
   ~TestIOThread();
 
@@ skipping 18 matching lines @@
   }
 
  private:
   base::Thread io_thread_;
   bool io_thread_started_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(TestIOThread);
 };
 
 }  // namespace test
+}  // namespace system
 }  // namespace mojo
 
-#endif  // MOJO_EDK_TEST_TEST_IO_THREAD_H_
+#endif  // MOJO_EDK_SYSTEM_TEST_TEST_IO_THREAD_H_