Make asBlur method const.
http://codereview.appspot.com/5190041/

This change makes asBlur const consistent with SkShader::asAGradient and asABitmap.


git-svn-id: http://skia.googlecode.com/svn/trunk@2404 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed