Before this commit the object that #this would refer to in
nested expressions within projection/selection clauses was always
the root context object. This was incorrect as it should be the
element being projected/selected over. This commit introduces
a scope root context object which is set upon entering a new
scope (like when entering a projection or selection). Any
object. With this change this kind of expression now behaves:
where #this is the element of list1. Unqualified references
are also resolved against this scope root context object.
Issues: SPR-10417, SPR-12035, SPR-13055
91ed5b6b8c