Removed most of the bogus CompilationInfo constructor calls.

Removed most of the bogus CompilationInfo constructor calls.

A CompilationInfo constructed from just an Isolate* and a Zone* is in
weird an inconsistent state (calling e.g. flags() on it will crash),
so we need to avoid them. This CL removes almost all of them, the
remaining 2 call sites in (for testing only) will be handled in a
separate CL. Things which have been changed:

  * Linkage is basically a decorator for CallDescriptor now.

  * ChangeLowering doesn't need Linkage at all.

  * JSGenericLowering doesn't need a full CompilationInfo*, just a
    single flag.

  * JSContextSpecializer doesn't need the full CompilationInfo, just a
    Context.

  * Removed unused CompilationInfo from SimplifiedLoweringTester.

This nicely decouples things already a bit more, but there's still
work to do...

Committed: https://crrev.com/d1b5aa0716752e328102fb7b0780d750c08a3673
Cr-Commit-Position: refs/heads/master@{#26580}

[Sven Panne, 2015-02-11 13:37:44]

svenpanne@chromium.org changed reviewers:
+ dcarney@chromium.org

[dcarney, 2015-02-11 13:41:12]

lgtm

[Sven Panne, 2015-02-11 13:42:35]

The CQ bit was checked by svenpanne@chromium.org

[commit-bot: I haz the power, 2015-02-11 13:43:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/899803003/1

[commit-bot: I haz the power, 2015-02-11 14:12:08]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-11 14:12:21]

Patchset 1 (id:??) landed as
https://crrev.com/d1b5aa0716752e328102fb7b0780d750c08a3673
Cr-Commit-Position: refs/heads/master@{#26580}