Fix for crash in SkDeferredCanvas when optional SkPaint argument is NULL

BUG=http://code.google.com/p/skia/issues/detail?id=505
TEST=Canvas unit test
REVIEW=http://codereview.appspot.com/5699054/



git-svn-id: http://skia.googlecode.com/svn/trunk@3246 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed