This patch removes Promise functions and methods which are absent
from the ES2015 specification when the --es-staging flag is on.
The patch is being relanded after being reverted due to an
unrelated bug. This version is slightly different as promise_chain
is installed on the context regardless of the flag value, so that
the Promise::Chain API continues to work until it is deprecated.

BUG=v8:3237
R=rossberg
LOG=Y

Review URL: https://codereview.chromium.org/1513873002

Cr-Commit-Position: refs/heads/master@{#32772}