Update V8 to version 4.8.71.
Update V8 to version 4.8.71.

Summary of changes available at:
https://chromium.googlesource.com/v8/v8/+log/57e3f62d..1ec2c8a8

Please follow these instructions for assigning/CC'ing issues:
https://code.google.com/p/v8-wiki/wiki/TriagingIssues

Please close rolling in case of a roll revert:
https://v8-roll.appspot.com/

TBR=hablich@chromium.org,machenbach@chromium.org,yangguo@chromium.org,vogelheim@chromium.org

Review URL: https://codereview.chromium.org/1404093005

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#354280}

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