Remove unnecessary environment from LStoreKeyedFastElements.

Remove unnecessary environment from LStoreKeyedFastElements.

This was a left-over from a time when bounds-check was performed
as part of this instruction.

I also refactored and improved the code for smi-only arrays.

R=vegorov@chromium.org
Committed: http://code.google.com/p/v8/source/detail?r=10300

[fschneider, 2011-12-22 16:00:03]

Ready for review.

cc'ed danno for the smi-only-arrays part.

http://codereview.chromium.org/9023006/diff/1007/src/hydrogen.cc
File src/hydrogen.cc (left):

http://codereview.chromium.org/9023006/diff/1007/src/hydrogen.cc#oldcode4403
src/hydrogen.cc:4403: AddInstruction(new(zone()) HCheckSmi(val));
This check becomes redundant because there is now one generated in
BuildFastElementAccess.

[Vyacheslav Egorov (Chromium), 2011-12-22 16:22:09]

lgtm