Use one scoped_refptr.

webrtc/modules/audio_device/win/audio_device_core_win.cc

Index: webrtc/modules/audio_device/win/audio_device_core_win.cc
diff --git a/webrtc/modules/audio_device/win/audio_device_core_win.cc b/webrtc/modules/audio_device/win/audio_device_core_win.cc
index f792a7169287caab09519f98a54872a885ec2904..9931e9afe3412f42dc3c501d3aef235da29d1b95 100644
--- a/webrtc/modules/audio_device/win/audio_device_core_win.cc
+++ b/webrtc/modules/audio_device/win/audio_device_core_win.cc
@@ -4205,7 +4205,7 @@ int AudioDeviceWindowsCore::SetDMOProperties()
     HRESULT hr = S_OK;
     assert(_dmo != NULL);
 
-    scoped_refptr<IPropertyStore> ps;
+    rtc::scoped_refptr<IPropertyStore> ps;
     {
         IPropertyStore* ptrPS = NULL;
         hr = _dmo->QueryInterface(IID_IPropertyStore,
@@ -4638,7 +4638,7 @@ int32_t AudioDeviceWindowsCore::_GetDefaultDeviceIndex(EDataFlow dir,
     for (UINT i = 0; i < count; i++)
     {
         memset(szDeviceID, 0, sizeof(szDeviceID));
-        scoped_refptr<IMMDevice> device;
+        rtc::scoped_refptr<IMMDevice> device;
         {
             IMMDevice* ptrDevice = NULL;
             hr = collection->Item(i, &ptrDevice);