Move symbol-table parameter setup inside FunctionDeclaration.

Previously, this was a group effort shared by the Parser and
DSLFunction.

Change-Id: Ibe84f3584887f288b5515057f5be9df73605d8b3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/698841
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
6 files changed