Port 34b7b21d

Original commit message:
    If inline allocation fails, we can just use the %NewObject fallback,
    which will do the right thing. We don't need a dedicated fallback to
    %AllocateInNewSpace.

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

Review URL: https://codereview.chromium.org/1448063002

Cr-Commit-Position: refs/heads/master@{#32015}