Refactor how the DeviceMonitor is started.

content/browser/media/media_devices_monitor.cc

Index: content/browser/media/media_devices_monitor.cc
diff --git a/content/browser/media/media_devices_monitor.cc b/content/browser/media/media_devices_monitor.cc
index c34bd5030a44ceb0f38633c9a745eb4cf827a12b..9f2c18353f186d31b28010fd2ee40e498fa90336 100644
--- a/content/browser/media/media_devices_monitor.cc
+++ b/content/browser/media/media_devices_monitor.cc
@@ -12,10 +12,7 @@ namespace content {
 namespace {
 void EnsureMonitorCaptureDevicesInternal(
     MediaStreamManager* media_stream_manager) {
-  // TODO(perkj): The argument list suggests that this is the wrong design. Can
-  // we add a separate method for device monitoring?
-  media_stream_manager->EnumerateDevices(
-      NULL, -1, -1, NULL, -1, MEDIA_DEVICE_AUDIO_CAPTURE, GURL());
+  media_stream_manager->EnsureDeviceMonitorStarted();
 }
 }