ccpr: Age out path cache entries

Adds a hook that gets called from GrContext::performDeferredCleanup.

Bug: skia:8452
Change-Id: I4e5f4d263528b21247fbc032a1b4881a23cbb2ff
Reviewed-on: https://skia-review.googlesource.com/c/167181
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
5 files changed