Revert of Switch to STA mode for audio thread and WASAPI I/O streams.

media/audio/win/core_audio_util_win_unittest.cc

Index: media/audio/win/core_audio_util_win_unittest.cc
diff --git a/media/audio/win/core_audio_util_win_unittest.cc b/media/audio/win/core_audio_util_win_unittest.cc
index 1a24e5d29be117348a96155219ad3ec881cb223b..31f91e91cf5515c7732c6e065b2bb9fdcc0c447c 100644
--- a/media/audio/win/core_audio_util_win_unittest.cc
+++ b/media/audio/win/core_audio_util_win_unittest.cc
@@ -19,10 +19,13 @@
 
 class CoreAudioUtilWinTest : public ::testing::Test {
  protected:
-  // The test runs on a COM thread in the singlethreaded apartment (STA).
+  // The test runs on a COM thread in the multithreaded apartment (MTA).
   // If we don't initialize the COM library on a thread before using COM,
   // all function calls will return CO_E_NOTINITIALIZED.
-  CoreAudioUtilWinTest() { DCHECK(com_init_.succeeded()); }
+  CoreAudioUtilWinTest()
+      : com_init_(ScopedCOMInitializer::kMTA) {
+    DCHECK(com_init_.succeeded());
+  }
   virtual ~CoreAudioUtilWinTest() {}
 
   bool DevicesAvailable() {