X87: [es6] Introduce spec compliant IsConstructor.

X87: [es6] Introduce spec compliant IsConstructor.

port 8fe3ac07014ce5891be0a1cbd8019e9f3b02ff0b (30902).

original commit message:

    There was already a bit on the Map named "function with prototype",
    which basically meant that the Map was a map for a JSFunction that could
    be used as a constructor. Now this CL generalizes that bit to
    IsConstructor, which says that whatever (Heap)Object you are looking at
    can be used as a constructor (i.e. the bit is also set for bound
    functions that can be used as constructors and proxies that have a
    [[Construct]] internal method).

    This way we have a single chokepoint for IsConstructor checking, which
    allows us to get rid of the various ways in which we tried to guess
    whether something could be used as a constructor or not.

    Drive-by-fix: Renamed IsConstructor on FunctionKind to
    IsClassConstructor to resolve the weird name clash, and the
    IsClassConstructor name also matches the spec.

BUG=

Committed: https://crrev.com/11fd60f5a9b5925843fe2160025f1fd8b68cf9c8
Cr-Commit-Position: refs/heads/master@{#30908}

[chunyang.dai, 2015-09-24 10:11:00]

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

[chunyang.dai, 2015-09-24 10:11:00]

PTAL

[Weiliang, 2015-09-24 10:15:04]

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

[Weiliang, 2015-09-24 10:15:05]

lgtm

[commit-bot: I haz the power, 2015-09-24 10:15:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1362313002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1362313002/1

[commit-bot: I haz the power, 2015-09-24 10:46:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-24 10:46:25]

Patchset 1 (id:??) landed as
https://crrev.com/11fd60f5a9b5925843fe2160025f1fd8b68cf9c8
Cr-Commit-Position: refs/heads/master@{#30908}