Cache text blobs computed by TextLine::paintText

Change-Id: I7d4414fb64b14a714623e4c20199cab06e6ed18c
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/342297
Commit-Queue: Jason Simmons <jsimmons@google.com>
Reviewed-by: Julia Lavrova <jlavrova@google.com>
2 files changed