Resource::create(Raw) creates Resource, not RawResource.
This breaks the assumption that a Resource with type Resource::Raw is always RawResource, and causes illegal downcasts e.g. from Resource to RawResource.
This causes CFI bot failures:
https://codereview.chromium.org/2391523002/#msg30
Comment 1 by bugdroid1@chromium.org
, Oct 6 2016