Remove attach and detach glyph cache.

BUG=skia:7515

Change-Id: Ib978e3cf4cfffdefe6453feb520e5e73684abf2e
Reviewed-on: https://skia-review.googlesource.com/112560
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Herb Derby <herb@google.com>
13 files changed