Handle all InstanceTypes in BitsetType::Lub().
Handle all InstanceTypes in BitsetType::Lub().

JS_ITERATOR_RESULT_TYPE was missing but required (repro: load inbox.google.com with a Debug build).

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1302313013

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#30586}

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh