Remove HLoadElements instruction and replace with use of more general HLoadNamedField.

Remove HLoadElements instruction and replace with use of more general HLoadNamedField. This removes the need for both the hydrogen and lithium instructions and allows both kinds of loads to be GVN'd.

Committed: https://code.google.com/p/v8/source/detail?r=14542

[titzer, 2013-05-03 10:52:10]

(Sorry for the new issue, I based the first issue off a mistaken commit to my
local master).

[Michael Starzinger, 2013-05-03 12:05:10]

LGTM with one nit.

https://codereview.chromium.org/14556020/diff/1/.gitignore
File .gitignore (right):

https://codereview.chromium.org/14556020/diff/1/.gitignore#newcode27
.gitignore:27: bsuite
Obsolete change, let's drop this.

[titzer, 2013-05-03 12:21:31]

Committed patchset #1 manually as r14542 (presubmit successful).