animation timing. This allows us to "freeze" time in order to do things like
draw multiple times to test clipping.
git-svn-id: http://skia.googlecode.com/svn/trunk@444 2bbb7eff-a529-9590-31e7-b0007b416f81
existing obj->safeRef(), which is unsafe since it can its 'if (this)' can be
optimized away by some compilers.
fix some overflows in mimpmap generation
git-svn-id: http://skia.googlecode.com/svn/trunk@181 2bbb7eff-a529-9590-31e7-b0007b416f81