Scoping for initializers is yet incorrect. Defaults are not supported.

R=arv@chromium.org,rossberg@chromium.org
BUG=v8:811
LOG=N

Committed: https://crrev.com/42f30f4ded2b1ca0c4caa7639e6206e93c78ee70
Cr-Commit-Position: refs/heads/master@{#29184}

Review URL: https://codereview.chromium.org/1189743003

Cr-Commit-Position: refs/heads/master@{#29192}