X87: Use platform specific stubs for vector-based Load/KeyedLoad.

X87: Use platform specific stubs for vector-based Load/KeyedLoad.

port 34a1a76ddf30109f7b6cb60aa2651493ab38660a (r27235)

original commit message:

  A hydrogen code stub is not the best approach because it builds a frame
  and doesn't have the technology to discard roots at tail call exits.
  Platform-specific stubs provide much better performance at this point.

BUG=

Committed: https://crrev.com/40de9c3f02d9659b83f3fa5340132adf54e50223
Cr-Commit-Position: refs/heads/master@{#27394}

[chunyang.dai, 2015-03-23 10:06:47]

chunyang.dai@intel.com changed reviewers:
+ weiliang.lin@intel.com

[chunyang.dai, 2015-03-23 10:06:47]

PTAL.

[Weiliang, 2015-03-24 09:46:53]

The CQ bit was checked by weiliang.lin@intel.com

[Weiliang, 2015-03-24 09:46:53]

lgtm

[commit-bot: I haz the power, 2015-03-24 09:47:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1025073005/1

[commit-bot: I haz the power, 2015-03-24 10:06:12]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-24 10:06:31]

Patchset 1 (id:??) landed as
https://crrev.com/40de9c3f02d9659b83f3fa5340132adf54e50223
Cr-Commit-Position: refs/heads/master@{#27394}