MIPS: A performance regression in array literal creation was caused by refactoring.

Port r18046 (99c7352)

Original commit message:
A performance regression in array literal creation was caused by refactoring that eliminated a special fast case for shallow arrays. At the same time the general case got a bit slower. This CL restores most of the performance without coding the special fast case. The virtual dispatching is unnecessary because we know what we want to do at compile time. A flag was added to Runtime::CreateArrayLiteral. The flags delivers information about shallowness but also whether or not allocation mementos should be created. This is useful for crankshafted code.

BUG=v8:3008
LOG=Y
R=gergely@homejinni.com

Review URL: https://codereview.chromium.org/85633004

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

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18064 ce2b1a6d-e550-0410-aec6-3dcde31c8c00