Adding experimental exclusive-mode streaming to WASAPIAudioOutputStream

media/audio/win/audio_manager_win.cc

Index: media/audio/win/audio_manager_win.cc
diff --git a/media/audio/win/audio_manager_win.cc b/media/audio/win/audio_manager_win.cc
index 38c461536c5bb2b787f99078d3664b74adc51cf6..2f4ea80162204a270550737de449c9918a2c8465 100644
--- a/media/audio/win/audio_manager_win.cc
+++ b/media/audio/win/audio_manager_win.cc
@@ -26,6 +26,7 @@
 #include "media/audio/win/wavein_input_win.h"
 #include "media/audio/win/waveout_output_win.h"
 #include "media/base/limits.h"
+#include "media/base/media_switches.h"
 
 // Libraries required for the SetupAPI and Wbem APIs used here.
 #pragma comment(lib, "setupapi.lib")
@@ -269,7 +270,16 @@ AudioOutputStream* AudioManagerWin::MakeLowLatencyOutputStream(
   } else {
     // TODO(henrika): improve possibility to specify audio endpoint.
     // Use the default device (same as for Wave) for now to be compatible.
-    stream = new WASAPIAudioOutputStream(this, params, eConsole);
+    const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
+    if (cmd_line->HasSwitch(switches::kEnableExclusiveMode)) {
+      // Experiemental mode; use with care.
+      stream = new WASAPIAudioOutputStream(
+          this, params, eConsole, AUDCLNT_SHAREMODE_EXCLUSIVE);
+    } else {
+      // Shared mode streaming is the default mode.
+      stream = new WASAPIAudioOutputStream(
+          this, params, eConsole, AUDCLNT_SHAREMODE_SHARED);
+    }
   }
 
   return stream;