Fix crash when editing particle scripts

If the scripts fail to produce valid bytecode, don't overwrite the
interpreter.

Change-Id: Icd008a5188166ce086ff4df87dcb2b43d7f80820
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/269487
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed