Get rid of hasAccessorProperty in Heap::Base

Get rid of hasAccessorProperty in Heap::Base

This shouldn't affect performance as we can just as well
check for cases where we need to take the slow path
differently.

Change-Id: I4b9f69c39e9e64b437820ca3a6ea43e8877f2cf3
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>