[PDF] Fix fallout from r1217.

The width and height we pass to SkDevice must be postive.
Shader can no longer use negative coordinates (without transform).
Shader unflip matrix should use same values as passed to SkPDFDevice (height).
Most Shader dictionary entries should be scalars and not ints.

Review URL: http://codereview.appspot.com/4454047

git-svn-id: http://skia.googlecode.com/svn/trunk@1219 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed