Fixed issues found by fuzzer

Last week, the fuzzer found a few numerical issue with filters and I had written some fixes for them. Here are the fixes with some unit tests.

For senorblanco : So I figured out what was asserting when we'd get a 0 width "result" in SkBicubicImageFilter::onFilterImage(). Basically, if the "result" SkBitmap object calls SkBitmap::setConfig() with "width" and/or "height" set to 0, then the SkBitmap object will call SkBitmap::reset(), making the SkBitmap object's config invalid. At this point, calling SkBitmap::getAddr32() will assert, even without attempting to dereference the data pointer, because the SkBitmap's config is invalid. If height is valid, but width is 0, then this call to SkBitmap::getAddr32() happens directly in SkBicubicImageFilter::onFilterImage() a few lines lower and asserts right away.

BUG=
R=senorblanco@google.com, senorblanco@chromium.org, bsalomon@google.com

Author: sugoi@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23533042

git-svn-id: http://skia.googlecode.com/svn/trunk/include@11249 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed