Disable handle zapping on 4.2 branch

BUG=chromium:318206
LOG=n
TBR=jochen@chromium.org

Review URL: https://codereview.chromium.org/946503005

Cr-Commit-Position: refs/branch-heads/4.2@{#2}
Cr-Branched-From: 3dfd929e-refs/heads/4.2.77@{#2}
Cr-Branched-From: e0110920-refs/heads/master@{#26757}