[d8 Workers] Make Worker prototype read-only

[d8 Workers] Make Worker prototype read-only

BUG=chromium:518747
R=mstarzinger@chromium.org
LOG=n

Committed: https://crrev.com/cd9293445e69c51846795fe9f526e970585a1423
Cr-Commit-Position: refs/heads/master@{#30099}

[Michael Starzinger, 2015-08-10 21:57:37]

LGTM. Should we add a regression test?

[binji, 2015-08-10 22:05:15]

On 2015/08/10 at 21:57:37, mstarzinger wrote:
> LGTM. Should we add a regression test?

Whoops, forgot to git add. :)

[binji, 2015-08-11 00:14:51]

The CQ bit was checked by binji@chromium.org

[binji, 2015-08-11 00:14:51]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/1277543006/#ps20001
(title: "add test")

[commit-bot: I haz the power, 2015-08-11 00:15:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1277543006/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1277543006/20001

[commit-bot: I haz the power, 2015-08-11 00:17:05]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-08-11 00:17:20]

Patchset 2 (id:??) landed as
https://crrev.com/cd9293445e69c51846795fe9f526e970585a1423
Cr-Commit-Position: refs/heads/master@{#30099}