Remove unused (by clients) SkUnitMapper (https://codereview.chromium.org/283273002/)

This reverts commit dd50c83b5b34dab3a077741861b50ed1f2bc6b8f.

BUG=skia:
R=scroggo@google.com

Author: reed@google.com

Review URL: https://codereview.chromium.org/288343009

git-svn-id: http://skia.googlecode.com/svn/trunk@14830 2bbb7eff-a529-9590-31e7-b0007b416f81
47 files changed