[turbofan] Sanitize typing rules for function calls.

[turbofan] Sanitize typing rules for function calls.

Currently we (mostly) infer FunctionType for JSFunction constants, and
match the FunctionType in the typing rule for JSCallFunction. This has
several drawbacks for JavaScript, especially we don't have Constant
types for global functions (i.e. String, Object, Reflect and friends).
Plus the FunctionType magic doesn't actually buy us anything. So this
changes the typing rule for HeapConstant constant to actually infer
Constant types for JSFunction objects and moves the recognition of
builtin functions to the typing rule for JSCallFunction.

Also adapts the specialized lowering in JSTypedLowering to Constant
functions instead of FunctionType, which has the additional advantage
that we can do the receiver wrapping/converting based on the (known)
SharedFunctionInfo.

R=jarin@chromium.org

Committed: https://crrev.com/3fbbfc38c22d123c629722a7c29cee952c7ad1d2
Cr-Commit-Position: refs/heads/master@{#31553}

[Benedikt Meurer, 2015-10-26 09:01:31]

Hey Jaro,

As discussed offline, FunctionType is not used anymore (also partially reverting
a change I did several months ago).
Please take a look.

Thanks,
Benedikt

[Jarin, 2015-10-26 10:04:25]

lgtm, cc'ing Andreas.

[Benedikt Meurer, 2015-10-26 10:04:41]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2015-10-26 10:04:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1420093005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1420093005/1

[rossberg, 2015-10-26 10:20:29]

LGTM. Do we still need FunctionType at all?

[commit-bot: I haz the power, 2015-10-26 10:28:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-26 10:29:07]

Patchset 1 (id:??) landed as
https://crrev.com/3fbbfc38c22d123c629722a7c29cee952c7ad1d2
Cr-Commit-Position: refs/heads/master@{#31553}