SDL-1.2: testtimer: Check removing bogus timers

From c497db14c187c932ec403058acefa8e970d8ed43 Mon Sep 17 00:00:00 2001
From: Cameron Cawley <[EMAIL REDACTED]>
Date: Fri, 23 Sep 2022 16:17:51 +0100
Subject: [PATCH] testtimer: Check removing bogus timers

Change from libsdl-org/sdl12-compat@10fe724eb2698f6b2925db1421a8c5bb6af7c8b7 and libsdl-org/sdl12-compat@807814398fb5bcd861eb2891e83fcb8421cd0a24
---
 test/testtimer.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/testtimer.c b/test/testtimer.c
index 95608c120..591133995 100644
--- a/test/testtimer.c
+++ b/test/testtimer.c
@@ -82,6 +82,13 @@ int main(int argc, char *argv[])
 	SDL_RemoveTimer(t2);
 	SDL_RemoveTimer(t3);
 
+	printf("Removing bogus timer...");
+	if (SDL_RemoveTimer(t1)) {
+		printf("UHOH, SHOULD HAVE FAILED\n");
+	} else {
+		printf("OK!\n");
+	}
+
 	SDL_Quit();
 	return(0);
 }