Introduce two new text properties to control the font size range when
auto-scaling text:
- plumb new json props ('mf' -- minimum font size, 'xf' -- maximum
font size)
- update the scale-to-fit binary search to use the specified extremes
Change-Id: I9e7e4915936a0be74bea473a520cf75acc05c84b
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/404781
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Mike Reed <reed@google.com>