mstask: ITaskTrigger::SetTrigger() should fail on NULL input.

dlls/mstask/task_trigger.c

@@ -103,6 +103,8 @@ static HRESULT WINAPI MSTASK_ITaskTrigger_SetTrigger(
 
     TRACE("(%p, %p)\n", iface, pTrigger);
 
+    if (!pTrigger) return E_INVALIDARG;
+
     /* Verify valid structure size */
     if (pTrigger->cbTriggerSize != sizeof(*pTrigger))
         return E_INVALIDARG;

dlls/mstask/tests/task_trigger.c

@@ -136,6 +136,9 @@ static void test_SetTrigger_GetTrigger(void)
     hres = ITask_CreateTrigger(test_task, &idx, &test_trigger);
     ok(hres == S_OK, "got %#x\n", hres);
 
+    hres = ITaskTrigger_SetTrigger(test_trigger, NULL);
+    ok(hres == E_INVALIDARG, "got %#x\n", hres);
+
     /* Setup a trigger with base values for this test run */
     GetLocalTime(&time);
     empty_trigger_state.wStartHour = time.wHour;