cros: Fix video unittests on cros device.

media/gpu/video_decode_accelerator_unittest.cc

 // Copyright (c) 2012 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.
 //
 // The bulk of this file is support code; sorry about that.  Here's an overview
 // to hopefully help readers of this code:
 // - RenderingHelper is charged with interacting with X11/{EGL/GLES2,GLX/GL} or
 //   Win/EGL.
 // - ClientState is an enum for the state of the decode client used by the test.
 // - ClientStateNotification is a barrier abstraction that allows the test code
@@ skipping 250 matching lines @@
 // for all test cases.
 class VideoDecodeAcceleratorTestEnvironment : public ::testing::Environment {
  public:
   VideoDecodeAcceleratorTestEnvironment()
       : rendering_thread_("GLRenderingVDAClientThread") {}
 
   void SetUp() override {
     base::Thread::Options options;
 #if defined(OS_WIN)
     options.message_loop_type = base::MessageLoop::TYPE_UI;
+#elif defined(USE_OZONE)
+    // Some ozone platforms (e.g. drm) expects to be able to watch a file
+    // handler from this thread. So use the IO type message loop here.
+    options.message_loop_type = base::MessageLoop::TYPE_IO;
 #endif
     rendering_thread_.StartWithOptions(options);
 
     base::WaitableEvent done(base::WaitableEvent::ResetPolicy::AUTOMATIC,
                              base::WaitableEvent::InitialState::NOT_SIGNALED);
     rendering_thread_.task_runner()->PostTask(
         FROM_HERE, base::Bind(&RenderingHelper::InitializeOneOff, &done));
     done.Wait();
 
 #if defined(USE_OZONE)
@@ skipping 1630 matching lines @@
       media::g_thumbnail_output_dir = base::FilePath(it->second.c_str());
     }
   }
 
   base::ShadowingAtExitManager at_exit_manager;
 
   return base::LaunchUnitTestsSerially(
       argc, argv,
       base::Bind(&media::VDATestSuite::Run, base::Unretained(&test_suite)));
 }