[crankshaft] Fix interceptor shadowing constant global property.

[crankshaft] Fix interceptor shadowing constant global property.

This makes sure Crankshaft respects interceptors in the global object
even when they shadow a constant global property.

R=verwaest@chromium.org
TEST=cctest/test-api-interceptors/PrePropertyHandler

Committed: https://crrev.com/7196ea72c8d77944108b9e38c4f084ef2b8b79ad
Cr-Commit-Position: refs/heads/master@{#27733}

[Toon Verwaest, 2015-04-09 18:10:20]

lgtm

[Michael Starzinger, 2015-04-10 08:29:23]

The CQ bit was checked by mstarzinger@chromium.org

[Michael Starzinger, 2015-04-10 08:29:23]

The patchset sent to the CQ was uploaded after l-g-t-m from
verwaest@chromium.org
Link to the patchset: https://codereview.chromium.org/1070803002/#ps20001
(title: "Rebased.")

[commit-bot: I haz the power, 2015-04-10 08:29:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1070803002/20001

[commit-bot: I haz the power, 2015-04-10 08:30:46]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-04-10 08:30:58]

Patchset 2 (id:??) landed as
https://crrev.com/7196ea72c8d77944108b9e38c4f084ef2b8b79ad
Cr-Commit-Position: refs/heads/master@{#27733}