The theory is nice, but once you enable it this won't work in OpenGL ES 2.0 as it has no integers or bitwise operators. A multiplication instead might make it work for cases where the mask is only constructed of 00 and FF (on and off).

Of course, this can indeed be done right in OpenGL ES 3.0 or OpenGL on the desktop in the future.

But it's okay to commit as is to show intention, as it's commented out.