Add IPC to query capabilities of video input devices.

content/renderer/media/media_devices_event_dispatcher_unittest.cc

Index: content/renderer/media/media_devices_event_dispatcher_unittest.cc
diff --git a/content/renderer/media/media_devices_event_dispatcher_unittest.cc b/content/renderer/media/media_devices_event_dispatcher_unittest.cc
index 733f512d2c05a7be71bedc93522b4c7c66f4dc41..8d2d975b824e1670ad4a375ca7a300492ae54779 100644
--- a/content/renderer/media/media_devices_event_dispatcher_unittest.cc
+++ b/content/renderer/media/media_devices_event_dispatcher_unittest.cc
@@ -47,6 +47,9 @@ class MockMediaDevicesDispatcherHost
                     const url::Origin& security_origin));
   MOCK_METHOD2(UnsubscribeDeviceChangeNotifications,
                void(MediaDeviceType type, uint32_t subscription_id));
+  MOCK_METHOD2(GetVideoInputCapabilities,
+               void(const url::Origin& security_origin,
+                    const GetVideoInputCapabilitiesCallback& client_callback));
 
   ::mojom::MediaDevicesDispatcherHostPtr CreateInterfacePtrAndBind() {
     return binding_.CreateInterfacePtrAndBind();