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

Review URL: http://codereview.chromium.org//7262026
Patch from Paul Lind <plind44@gmail.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8427 ce2b1a6d-e550-0410-aec6-3dcde31c8c00