qedit/tests: Add some tests for null renderer pin interfaces.

dlls/qedit/tests/nullrenderer.c

@@ -59,6 +59,7 @@ static void test_interfaces(void)
 {
     IBaseFilter *filter = create_null_renderer();
     ULONG ref;
+    IPin *pin;
 
     check_interface(filter, &IID_IBaseFilter, TRUE);
     check_interface(filter, &IID_IMediaFilter, TRUE);
@@ -78,6 +79,18 @@ static void test_interfaces(void)
     check_interface(filter, &IID_IReferenceClock, FALSE);
     check_interface(filter, &IID_IVideoWindow, FALSE);
 
+    IBaseFilter_FindPin(filter, sink_id, &pin);
+
+    check_interface(pin, &IID_IMemInputPin, TRUE);
+    check_interface(pin, &IID_IPin, TRUE);
+    todo_wine check_interface(pin, &IID_IQualityControl, TRUE);
+    check_interface(pin, &IID_IUnknown, TRUE);
+
+    check_interface(pin, &IID_IKsPropertySet, FALSE);
+    check_interface(pin, &IID_IMediaPosition, FALSE);
+    todo_wine check_interface(pin, &IID_IMediaSeeking, FALSE);
+
+    IPin_Release(pin);
     ref = IBaseFilter_Release(filter);
     ok(!ref, "Got unexpected refcount %d.\n", ref);
 }