use else instead of else-if -- fixes 'possibly unused' warning

BUG=
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/18527003

git-svn-id: http://skia.googlecode.com/svn/trunk@9863 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed