Port 757221e5

Original commit message:

    Neither globals nor lookup slots can be hole-initialized anymore, thus
    removing some dead code from the code generators and runtime-scopes.

R=adamk@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2061443002
Cr-Commit-Position: refs/heads/master@{#36899}