[Chapel Merge] Revert "At Brad's suggestion, transform these oper

Branch: refs/heads/master
Revision: 1abafc3
Author: lydia-duncan
Log Message:

Merge pull request #17783 from lydia-duncan/revertIteratorMethod

Revert "At Brad's suggestion, transform these operators on iterators into methods"
[suggested by Brad, straight-forward and not reviewed]

This reverts #17551

This change was causing issues with --baseline testing because the this
type argument was not getting dead code eliminated and referred to
_iteratorRecord, a type that is not put into the generated code normally
(because it is the generic template for iterator records rather than a specific
instance). It is not strictly necessary for iterator records to use operator
methods rather than operator standalone functions, so just back out the changes
(and maybe investigate it more later)

Resolves Cray/chapel-private#1988
Resolves Cray/chapel-private#2047

Testing:
Passed full paratest with futures. Ran full baseline paratest with futures, which
revealed some remaining errors to work on in a separate PR

Modified Files:
M modules/internal/ChapelIteratorSupport.chpl

Compare: https://github.com/chapel-lang/chapel/compare/19d5221febd7...1abafc362f5c