SkPDF: more paths as rects

Motivation: Content streams are marginally smaller and easier to read
(for debugging).
Change-Id: Idb82276f512408c083a1001da217707fd2d48e49
Reviewed-on: https://skia-review.googlesource.com/24744
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
1 file changed