There are 2 possible states for the deferred symbol --
1) UNDEFINED -- This is the zero state, no deferred object is attached
   to this symbol. When we want to add a new deferred we directly
   attach it to this symbol.
2) symbol with attached deferred object -- New deferred objects are
   not attached to this symbol, but instead they are directly attached
   to the resolve, reject callback arrays. At this point, the deferred
   symbol's state is stale, and the deferreds should be read from the
   reject, resolve callbacks.

BUG=v8:5046

Review-Url: https://codereview.chromium.org/2018913004
Cr-Commit-Position: refs/heads/master@{#36623}