BUG=v8:7294,v8:8562

Change-Id: I1ed3b6d6a2fed2aee224e22ae8db5d76a52998a5
Reviewed-on: https://chromium-review.googlesource.com/c/1449731Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59301}