Port ba2077aa

Original commit message:
    Move the already existing fast case for %NewObject into a dedicated
    FastNewObjectStub that we can utilize in places where we would otherwise
    fallback to %NewObject immediately, which is rather expensive.

    Also use FastNewObjectStub as the generic implementation of JSCreate,
    which should make constructor inlining based on SharedFunctionInfo (w/o
    specializing to a concrete closure) viable soon.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=

Review URL: https://codereview.chromium.org/1714123002

Cr-Commit-Position: refs/heads/master@{#34169}