We can check if the instance type of an object is JS_PROMISE_TYPE to determine if it is a promise rather than test whether the property promise_state_symbol is present.

BUG=
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel

Review-Url: https://codereview.chromium.org/2091243002
Cr-Commit-Position: refs/heads/master@{#37283}