Add tests and extension verifying CHECK and ASSERT.

test/mjsunit/mjsunit.status

Index: test/mjsunit/mjsunit.status
diff --git a/test/mjsunit/mjsunit.status b/test/mjsunit/mjsunit.status
index a0b45a0f133dfd4f0cff1718f624fcab47f9b71e..4997753a9dc5cf49aab8a3af14dc3a3cc805a1fe 100644
--- a/test/mjsunit/mjsunit.status
+++ b/test/mjsunit/mjsunit.status
@@ -99,6 +99,11 @@
   ##############################################################################
   # Long running test that reproduces memory leak and should be run manually.
   'regress/regress-2073': [SKIP],
+
+  ##############################################################################
+  # Tests verifying CHECK and ASSERT.
+  'verify-check-false': [FAIL, NO_VARIANTS],
+  'verify-assert-false': [NO_VARIANTS, ['mode == release', PASS], ['mode == debug', FAIL]],
 }],  # ALWAYS
 
 ##############################################################################