return false if we can't scale, to force us to try to lock the original and then proceed

BUG=
R=wangxianzhu@chromium.org

Review URL: https://codereview.chromium.org/27382002

git-svn-id: http://skia.googlecode.com/svn/trunk@11789 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed