[turbofan] Make inlining independent of typing.

[turbofan] Make inlining independent of typing.

The JSInliner used to load the context from the JSFunction node at
runtime, which introduced a HeapConstant (because we had to materialize
the JSFunction after context specialization) and a LoadField operation,
independent whether the inlinee actually uses the context. This is
rather cumbersome currently, and therefore this is now changed to just
embed the context constant instead. Once we do inlining based on
SharedFunctionInfo rather than JSFunction, we should reconsider this
decision and come up with a proper heuristic.

BUG=v8:3952
LOG=n
R=mstarzinger@chromium.org

Committed: https://crrev.com/eacd6d8b7d175032b65aa65fa11c9419abdaa236
Cr-Commit-Position: refs/heads/master@{#27069}

[Benedikt Meurer, 2015-03-09 12:42:00]

PTAL

[Michael Starzinger, 2015-03-09 13:01:03]

LGTM.

[Benedikt Meurer, 2015-03-09 13:01:50]

Committed patchset #1 (id:1) manually as
eacd6d8b7d175032b65aa65fa11c9419abdaa236 (presubmit successful).

[commit-bot: I haz the power, 2015-03-09 13:01:57]

Patchset 1 (id:??) landed as
https://crrev.com/eacd6d8b7d175032b65aa65fa11c9419abdaa236
Cr-Commit-Position: refs/heads/master@{#27069}