PreParser / Parser consistency: Make PreParser aware of Zone and AstValueFactory.

PreParser / Parser consistency: Make PreParser aware of Zone and AstValueFactory.

Previously it just had hacks to have NULLs instead of them and pretended to know
nothing about Zone. The hacks provide no real benefit (probably historically
based on some weird misconception about the relationship between Zone and
Isolate), and make it harder for the PreParser to start to know more about
variables and scoping.

BUG=

Committed: https://crrev.com/5c56665059891cbacf43f6efe483582029442f0b
Cr-Commit-Position: refs/heads/master@{#26494}

[marja, 2015-02-06 15:00:21]

marja@chromium.org changed reviewers:
+ rossberg@chromium.org

[marja, 2015-02-06 15:00:22]

rossberg, ptal.

[rossberg, 2015-02-06 15:05:25]

lgtm

[marja, 2015-02-06 15:56:51]

The CQ bit was checked by marja@chromium.org

[commit-bot: I haz the power, 2015-02-06 15:57:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/909463003/20001

[commit-bot: I haz the power, 2015-02-06 15:58:41]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-06 15:58:55]

Patchset 2 (id:??) landed as
https://crrev.com/5c56665059891cbacf43f6efe483582029442f0b
Cr-Commit-Position: refs/heads/master@{#26494}