[graphite] Add plumbing for Android-specific Pipeline label

This is just the plumbing to get the Caps where it needs to be.
The following CL with enable the pretty printing to output the YCbCr sampler information in a more human readable format.

Bug: b/456438502
Change-Id: I57b9cd9909d0466e37654b7ee7c04ff2c2979bf7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1002636
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Thomas Smith <thomsmit@google.com>
16 files changed