be more careful about OOB source pixels in the scanline rescaler, and
less certain about why the standalone scaler might have faileds

BUG=
R=reed@google.com

Author: humper@google.com

Review URL: https://codereview.chromium.org/100473011

git-svn-id: http://skia.googlecode.com/svn/trunk/src@12619 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed