add default ctor for SkGlyphRect

Change-Id: I18bba62b999c3b8920daf831dc512837a23e29a0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/509785
Auto-Submit: Herb Derby <herb@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
1 file changed