Most backends don't like init-stmts with multiple VarDeclarations inside
them, so we no longer emit IR that does this. This lets us avoid doing
backend-level fixups.
Change-Id: Ide839de18953a73e0f9c7a690df59a7bc3523f89
Bug: skia:11860
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/398221
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>