Upgrade MacBookAir7.2 to macOS 10.14; rename jobs to include OS version

Also add a NativeFonts job for this bot so we have coverage of 10.14.

Change-Id: I8536d7725eb3492b59318695dd3ecadad76b68ff
Reviewed-on: https://skia-review.googlesource.com/c/194022
Reviewed-by: Eric Boren <borenet@google.com>
Commit-Queue: Ben Wagner <benjaminwagner@google.com>
16 files changed