Use proxy canvas size.

The old code just hard coded 1,1 as size. Instead use the size of the
proxy canvas.

Change-Id: Ib1ebc9339c98680ca350f26f8ec514f6782de8a4
Reviewed-on: https://skia-review.googlesource.com/9160
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Herb Derby <herb@google.com>
1 file changed