MIPS: Unify deoptimizer for JavaScript frames.

Port r14715 (84633474)

Original commit message:
This unifies the translation of an optimized frame to a full JavaScript
frame. Only the frame's context and fp register as well as alignment
padding are different on each architecture and can be factored out.

BUG=

Review URL: https://codereview.chromium.org/15291002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14717 ce2b1a6d-e550-0410-aec6-3dcde31c8c00