Fix matrix adjustment passed to filter processing.
When adjusting the CTM for filter use, we were subtracting off the
destination coordinates of the drawDevice() or drawSprite(). This is
not quite correct: we should subtract off the coordinates relative to
the device origin instead. This occurs when one filtered saveLayer() is
drawn inside another saveLayer(), both with non-zero origin.
This fixes layout test svg/batik/text/smallFonts.svg in Blink, and is
exercised by the provided unit test.
BUG=skia:
R=bsalomon@google.com
Review URL: https://codereview.chromium.org/
222723002
git-svn-id: http://skia.googlecode.com/svn/trunk@14029
2bbb7eff-a529-9590-31e7-
b0007b416f81