Reduce the number of inliner temporaries by swizzling.

Ideally the inliner would be smart enough to avoid creating a temporary
at all just for a swizzle, but a good first step is to create fewer of
them.

Change-Id: Icd6f86c294237488f7923dc787bb64a5f99bd0ac
Bug: skia:10737
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/318213
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
12 files changed