d3d9/tests: Mark the test_wndproc() tests failing randomly on Windows as flaky.

dlls/d3d9/tests/d3d9ex.c

@@ -3096,6 +3096,7 @@ static void test_wndproc(void)
         SetForegroundWindow(GetDesktopWindow());
         ok(!expect_messages->message, "Expected message %#x for window %#x, but didn't receive it, i=%u.\n",
                 expect_messages->message, expect_messages->window, i);
+        flaky_if(i == 0 || i == 1)
         ok(!windowposchanged_received, "Received WM_WINDOWPOSCHANGED but did not expect it, i=%u.\n", i);
         expect_messages = NULL;
 

dlls/d3d9/tests/device.c

@@ -4342,6 +4342,7 @@ static void test_wndproc(void)
         SetForegroundWindow(GetDesktopWindow());
         ok(!expect_messages->message, "Expected message %#x for window %#x, but didn't receive it, i=%u.\n",
                 expect_messages->message, expect_messages->window, i);
+        flaky_if(i == 0)
         ok(!windowposchanged_received, "Received WM_WINDOWPOSCHANGED but did not expect it, i=%u.\n", i);
         expect_messages = NULL;