[fuzzing] Add first pass SkParagraph fuzzing.

Rough first pass at SkParagraph fuzzing. Lots of things not yet fuzzed.
--FontCollection cribbed from SkParagraphTest
--Current flow:
---Fuzz ParagraphStyle
---Add text and style some random small number of times.
---Text is either ASCII, unicode, or 'Zalgo'.

Although there are many todos, want to go ahead and submit this
~unchanged so the existing test cases that have found bugs are
not invalidated by a changing binary.

Change-Id: I38adca5fa79cfb20068fdf2fb431f90de55a2afc
Bug: skia:10894
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/336438
Commit-Queue: Weston Tracey <westont@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
2 files changed