start to use font for measure, not paint

-- lots more where this came from

Bug: skia:2664
Change-Id: I8bb47f02c156b0b88fbb92fec73af0eb6641b1bf
Reviewed-on: https://skia-review.googlesource.com/c/173769
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Mike Reed <reed@google.com>
9 files changed