Encode "parenthesized" status of parenthesized Expressions to prevent
them from being treated as Patterns.

BUG=v8:4657, v8:811
LOG=N
R=rossberg@chromium.org, adamk@chromium.org, littledan@chromium.org

Review URL: https://codereview.chromium.org/1570793002

Cr-Commit-Position: refs/heads/master@{#33190}