Changed rules about sized internal formats on GLES3.

R=jvanverth@google.com

Author: bsalomon@google.com

Review URL: https://chromiumcodereview.appspot.com/22823006

git-svn-id: http://skia.googlecode.com/svn/trunk@10806 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed