Use a hash table to quickly locate the strike

The hash table maps descriptors to strikes. So, instead
of searching through the linked list, find the strike
directly.

Change-Id: I53c6fc72c009c35e3476fabd02cee9ee93145c64
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/272465
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
2 files changed