Translucency Effect supports isActive hook

The effect gets a set of boolean values to check whether it is active for
one of the categories (e.g. move resize, decorations).

This allows to easily check whether the effect is active at all, that is
if all values are at 1.0 the effect will never affect a window.

In all other cases it can be combined with looking at the available
windows to e.g. enable the effect for move resize only when there is a
window which is either moved or resized. This check is performed whenever
an action happens which could cause a window to become inactive.

BUG: 306262
FIXED-IN: 4.9.2