Copied, with permission, from https://codereview.chromium.org/1151853003/

Initial patch set is an unmodified copy, rebased on top of related fixes from
https://codereview.chromium.org/1158933002/

Subsequent patch sets contain fixes for remaining bugs in the CL.

BUG=v8:3956
LOG=N

Review URL: https://codereview.chromium.org/1152093003

Cr-Commit-Position: refs/heads/master@{#28760}