Port 8196c28a

Original commit message:
JSConstructStub for subclass constructors instead locates new.target in
a known location on the stack.

R=dslomov@chromium.org, dstence@us.ibm.com, michael_dawson@ca.ibm.com
BUG=

Review URL: https://codereview.chromium.org/1208443002

Cr-Commit-Position: refs/heads/master@{#29254}