Interesting bits:
- Removed some behavior that is now unreachable in the presence of
type errors.
- Made if_null_behavior_test not a multitest since it doesn't need to
be any more.
- Likewise, if_null_evaluation_order_test never needed to be a
multitest.
R=lrn@google.com
Review-Url: https://codereview.chromium.org/3003933002 .