Apply the CTM to the offset in the slow SkOffsetImageFilter path.

This was being done in the fast path, but not the slow path.

Since I had to rebaseline the offsetimagefilter GM anyway (to accomodate
the new test case), I added a red border around the intersection
of the (transformed) crop rect and clip rect in each sample, beyond
which no pixels should be drawn.

Chrome bug: https://code.google.com/p/chromium/issues/detail?id=346362

BUG=skia:
R=sugoi@google.com

Review URL: https://codereview.chromium.org/186643003

git-svn-id: http://skia.googlecode.com/svn/trunk@13656 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed