SkPDF: Do draw{Image,Bitmap} with maskfilter.

https://fiddle.skia.org/c/@skbug_237_drawImage_with_blur
BUG=skia:237
Change-Id: I50f65d428f254e3965a448a110edd39c0f7a937f
Reviewed-on: https://skia-review.googlesource.com/19027
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
2 files changed