Do not set GLOB_REF for invariant indirections (#65709)

Do not set GLOB_REF for invariant indirections (#65709)

The GTF_GLOB_REF flag in the compiler has the meaning that
the node marked with it produces a value that could be modified
by a call or an indirect store. It is used for optimizations
that need to know whether it is safe to reorder two trees.

Invariant indirections, by definition, always produce the
same value, and as such do not need to be marked with GLOB_REF.

Some nice diffs from args sorting: string literals can now
be put in the "late args" list directly (without a temp).