Fixed 'destroyed without being declared' error in DSLParser

Once we have created a DSLVar, we need to return it to avoid internal
errors.

Change-Id: I28dacf49e2f5219660ddbc6e21100e3fb0675742
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/445099
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
1 file changed