saturate when converting float to fixed

Bug:783205
Change-Id: I30997e413f03f6ce2f8a8998efd78e350bdb43e3
Reviewed-on: https://skia-review.googlesource.com/75982
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Mike Reed <reed@google.com>
1 file changed