Reland "Fix more new Clang warnings"

This is a reland of 3d5483a5474521b52896410c6648fe2513d47a4d

Original change's description:
> Fix more new Clang warnings
>
> Change-Id: I82a13744669a6b5c23e23e6a719ec79878114dab
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/418697
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Kevin Lubick <kjlubick@google.com>

Change-Id: I6a81630c09d7aed906196b28adced0bf0a88e18d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/418938
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
5 files changed