binding: Fixes the fallback mechanism of Document's named properties.
The old implementation only works for
a) there is a hidden prototype, and documentWrapper->GetPrototype()
actually returns itself, or
b) fallbacked attributes are data-type properties.
Since we made attributes be accessor-type properties _and_ removed
the hidden prototype, the old implementation no longer works.
Fixed the issue using V8's GetRealNamedPropertyInPrototypeChain().
BUG=619036
Review-Url: https://codereview.chromium.org/2065523002
Cr-Commit-Position: refs/heads/master@{#399461}
2 files changed
