MIPS: Reland r18714 'Unify calling to GenerateFastApiCallBody before stubbing it'.

Port r18762 (e8954e8)

BUG=
R=plind44@gmail.com

Review URL: https://codereview.chromium.org/142573003

Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18783 ce2b1a6d-e550-0410-aec6-3dcde31c8c00