This is in preparation for the addition of --harmony-destructuring-assignment. BUG=v8:811 LOG=n Review URL: https://codereview.chromium.org/1450193002 Cr-Commit-Position: refs/heads/master@{#32098}
R=rossberg BUG= Review URL: https://codereview.chromium.org/1415283003 Cr-Commit-Position: refs/heads/master@{#31507}
Adds an implementation of "do expression" parsing (https://webcache.googleusercontent.com/search?q=cache:MIGALjqPDNgJ:wiki.ecmascript.org/doku.php%3Fid%3Dstrawman:do_expressions+&cd=1&hl=en&ct=clnk&gl=us). This feature provides a way to evaluate a block of statements within an expression context, producing the resulting completion value. This is very helpful for implementing certain language features via desugaring. BUG=v8:4488 LOG=N R=adamk@chromium.org, bmeurer@chromium.org, rossberg@chromium.org, wingo@igalia.com Review URL: https://codereview.chromium.org/1399893002 Cr-Commit-Position: refs/heads/master@{#31428}
