MIPS: Support Smi in CompareIDAndBranch

Port r14842 (1c8d7430)

BUG=

Review URL: https://codereview.chromium.org/15917012

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14863 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
MIPS: Added old data space allocation infrastructure for pretenuring.

Port r14843 (2d8faca3)

BUG=

Review URL: https://codereview.chromium.org/16155006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14864 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
MIPS: Update the gap resolver to support Smi constants.

Port r14850 (787f0941)

BUG=

Review URL: https://codereview.chromium.org/16146005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14865 ce2b1a6d-e550-0410-aec6-3dcde31c8c00