• The following new feature is only supported by the Graphite backend.

• Allow clients to pass in a maximum time duration Skia should spend when purging purgeable resources from caches. Skia will purge available purgeable resources until all purgeable resources are removed or until the purge time has been surpassed, at which point we exit early.

• Clients can either call the Context or the Recorder's performDeferredCleanup(...) method with a max duration in microseconds. Following the current implementation pattern, durations passed in get converted to time points when calling in to the ResourceCache itself.

• Public API calls into performDeferredCleanup accept an optional stop time duration which is set to std::nullopt by default. This signifies no time limit for purging and means this change should not disrupt current client API calls nor impact existing functionality.