This allows the JSIntrinsicLowering to optimize the cloning of literal
boilerplate objects using either the FastCloneShallowArrayStub or the
FastCloneShallowObjectStub when applicable.

R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/1097963002

Cr-Commit-Position: refs/heads/master@{#27974}