fix bookmaker bot

Drawing image subsets too many times
causes fiddle to fail where it used
to succeed. Reduce the number of draws
for now to work around this.

TBR=jcgregorio@google.com
NOTRY=true
Docs-Preview: https://skia.org/?cl=143100
Bug: skia:8180
Change-Id: I2610dc7575ed0e6eec1ee3c88e1f9ccc7b6a716e
Reviewed-on: https://skia-review.googlesource.com/143100
Commit-Queue: Cary Clark <caryclark@skia.org>
Auto-Submit: Cary Clark <caryclark@skia.org>
Reviewed-by: Cary Clark <caryclark@skia.org>
3 files changed