X87: Refactor BreakLocationIterator

X87: Refactor BreakLocationIterator

port 1a608493e55eacf5c7569e2b1213da42eb0e6207 (r26983)

original commit message:

   Refactor BreakLocationIterator.

   We now have BreakLocation::Iterator to iterate via RelocIterator, and
   create a BreakLocation when we are done iterating. The reloc info is
   stored in BreakLocation in a GC-safe way and instantiated on demand.

BUG=

Committed: https://crrev.com/7f78e7b34782abefec152752a5475ac403857f48
Cr-Commit-Position: refs/heads/master@{#27003}

[chunyang.dai, 2015-03-05 02:45:34]

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

[chunyang.dai, 2015-03-05 02:45:35]

PTAL.

[Weiliang, 2015-03-05 05:18:13]

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

[Weiliang, 2015-03-05 05:18:13]

lgtm

[commit-bot: I haz the power, 2015-03-05 05:19:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/978183002/1

[commit-bot: I haz the power, 2015-03-05 05:41:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-05 05:41:20]

Patchset 1 (id:??) landed as
https://crrev.com/7f78e7b34782abefec152752a5475ac403857f48
Cr-Commit-Position: refs/heads/master@{#27003}