There are a couple of failing impala test cases: * [ ] Remove `--clos` flag from impala again * [ ] Remove `--clos` flag for impala in test script * [ ] Fix non-closure related test cases that fail if `clos` plugin is loaded * [ ] Fix `codegen/cconv/typed_cc/recursion.impala` * [ ] Fix `codegen/cconv/typed_cc/closure_rec.impala`