Port e678a0f9

Original commit message:
    Use %_ToLength for TO_LENGTH, implemented via a ToLengthStub
    that supports a fast path for small integers. Everything else is still
    handled in the runtime.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, dstence@us.ibm.com
BUG=v8:4494
LOG=n

Review URL: https://codereview.chromium.org/1412153003

Cr-Commit-Position: refs/heads/master@{#31384}