Fix additional cases of variable shadowing.

These changes will allow us to enable shadowed-variable warnings.

Change-Id: I24ee7e198c1c77b58836237c37557c00452680e1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/439476
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
9 files changed