This method is now dead code since we introduced PromiseReaction chains
as linked lists.

Bug: v8:7253, v8:7310
Change-Id: I505a23d9ba4de456dbeeba9e603e70218cf6e767
Reviewed-on: https://chromium-review.googlesource.com/897515Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51052}