X87: Don't MISS if you read the hole from certain FastHoley arrays.

X87: Don't MISS if you read the hole from certain FastHoley arrays.

port caeb9004f0bfc2a916fc63e9d27100a3110016d4 (r28056)

original commit message:
    If the array's map is the initial FastHoley array map, and the array prototype
    chain is undisturbed and empty of elements, then keyed loads can convert the
    load of a hole to undefined.

BUG=

Committed: https://crrev.com/77a2c15fb4016dfebf9cb5a1ef7e3c5c0b32f8ac
Cr-Commit-Position: refs/heads/master@{#28128}

[chunyang.dai, 2015-04-27 16:28:26]

chunyang.dai@intel.com changed reviewers:
+ mvstanton@chromium.org

[chunyang.dai, 2015-04-27 16:28:27]

PTAL.

[chunyang.dai, 2015-04-28 16:32:56]

chunyang.dai@intel.com changed reviewers:
+ danno@chromium.org

[chunyang.dai, 2015-04-28 16:32:57]

PTAL because the owner of X87 (Weiliang) asked for annual leave. 
Thanks.

[mvstanton, 2015-04-29 06:27:36]

lgtm

[chunyang.dai, 2015-04-29 10:10:21]

The CQ bit was checked by chunyang.dai@intel.com

[commit-bot: I haz the power, 2015-04-29 10:10:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1104073003/1

[commit-bot: I haz the power, 2015-04-29 10:34:24]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-29 10:34:39]

Patchset 1 (id:??) landed as
https://crrev.com/77a2c15fb4016dfebf9cb5a1ef7e3c5c0b32f8ac
Cr-Commit-Position: refs/heads/master@{#28128}