MIPS: port Better codegen for '<expression> === void <literal>'.

MIPS: port Better codegen for '<expression> === void <literal>'.

Ported r8420 (fd2ddbb)

Original commit message:
Detect the pattern in both, the full compiler and crankshaft and generate direct pointer
comparisons. Along the way I cleaned up 'typeof <expression> == <string literal>' comparisons
as well by lifting platform independent code and checking the symmetric case.
BUG=v8:1440
TEST=cctest/test-api.cc

Committed: http://code.google.com/p/v8/source/detail?r=8427

[Søren Thygesen Gjesse, 2011-06-27 08:44:09]

LGTM

Steven, could you please take a look as well?

[Søren Thygesen Gjesse, 2011-06-27 10:38:46]

I will commit it.