Merged r14509 into trunk branch.

MIPS: Allow setting debugger breakpoints on CompareNilICs

R=jkummerow@chromium.org
BUG=

Review URL: https://codereview.chromium.org/14664003

git-svn-id: https://v8.googlecode.com/svn/trunk@14510 ce2b1a6d-e550-0410-aec6-3dcde31c8c00