Add rehydration enumerator for ConstructorSplat.

This renumbers all the dehydrated data.

Change-Id: I94c58c7f0b36e9832f47151b9d350e66f9fa01cb
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/392118
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
8 files changed