[elements, turbofan] Implement simple GrowElements

[elements, turbofan] Implement simple GrowElements

Unlike Crankshaft, Turbofan does not provide a context when trying to grow
elements. Depending on the code path we might end up updating transitioning
elements kinds in allocation sites for which we need access to the current
context. Unlike GrowCapacityAndConvert, the newly introduced GrowCapacity simply
returns false in cases where map transitions are involved.

BUG=chromium:637279

[Camillo Bruni, 2016-08-16 13:01:54]

cbruni@chromium.org changed reviewers:
+ mlippautz@chromium.org

[Michael Lippautz, 2016-08-16 13:14:42]

Fixes the problem encountered with smaller pages! Thanks a lot. Karma++

[Camillo Bruni, 2016-08-16 13:16:21]

cbruni@chromium.org changed reviewers:
+ jkummerow@chromium.org

[Camillo Bruni, 2016-08-16 13:16:21]

PTAL.

[Jakob Kummerow, 2016-08-16 15:00:56]

Description was changed from

==========
[elements, turbofan] Implement simple GrowElements

Unlike Crankshaft, Turbofan does not provide a context when trying to grow
elements. Depending on the code path we might end up updating transitioning
elements kinds in allocation sites for which we need access to the current
context. Unlike GrowCapacityAndConvert, the newly introduce GrowCapicity simply
returns false in cases where map transitions are involved.

BUG=chromium:637279
==========

to

==========
[elements, turbofan] Implement simple GrowElements

Unlike Crankshaft, Turbofan does not provide a context when trying to grow
elements. Depending on the code path we might end up updating transitioning
elements kinds in allocation sites for which we need access to the current
context. Unlike GrowCapacityAndConvert, the newly introduced GrowCapacity simply
returns false in cases where map transitions are involved.

BUG=chromium:637279
==========

[Jakob Kummerow, 2016-08-16 15:15:01]

Looks good.

https://codereview.chromium.org/2244983004/diff/1/src/elements.cc
File src/elements.cc (right):

https://codereview.chromium.org/2244983004/diff/1/src/elements.cc#newcode895
src/elements.cc:895: if (object->map()->is_prototype_map() ||
To explain why this code does what it's doing, please add a comment to the tune
of the one you're deleting in runtime-array.cc, roughly:
// This function is intended to be called from optimized code. We don't want
// to trigger lazy deopts there, so refuse to handle cases that would.

https://codereview.chromium.org/2244983004/diff/1/src/objects.cc
File src/objects.cc (right):

https://codereview.chromium.org/2244983004/diff/1/src/objects.cc#newcode16084
src/objects.cc:16084: return false;
Did you mean to "return result" here?

[Jakob Kummerow, 2016-08-18 14:11:51]

Stealing this at mlippautz' request and landing it at
https://codereview.chromium.org/2252393002