FLIP: Fix use-after-free error with temporary transformations.

FLIP: Fix use-after-free error with temporary transformations.

The FLIP procedure keeps a reference to the  dictionary from before running
a procedure and then uses that reference after calling proc_commit().  When
temporary transformations are present, this dictionary disappears.  The
"SPLIT FILE  - vs procedures" test triggers this issue because it uses
FILTER, which is implemented as a temporary transformation.

This commit fixes the problem by avoiding a reference to the old
dictionary after proc_commit().

Reported by John Darrington.
Bug #38820.