tests: add possibility to disable leak check for single test

In tests that are using external libraries (i. e. pthread) we
can get failure because of leaks in the external library.
Until we have some better solution (if ever), let these (and only these)
tests to disable leak checks.

Signed-off-by: Marek Chalupa <mchqwerty@gmail.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>

tests/sanity-test.c

@@ -81,6 +81,19 @@ FAIL_TEST(sanity_malloc_direct)
 	free(NULL);	/* NULL must not be counted */
 }
 
+TEST(disable_leak_checks)
+{
+	volatile void *mem;
+	assert(leak_check_enabled);
+	/* normally this should be on the beginning of the test.
+	 * Here we need to be sure, that the leak checks are
+	 * turned on */
+	DISABLE_LEAK_CHECKS;
+
+	mem = malloc(16);
+	assert(mem);
+}
+
 FAIL_TEST(sanity_malloc_indirect)
 {
 	struct wl_array array;