am 28e89fed: am a493be58: don\'t capture hidden layers in screenshots

        const Layer::State& state(layer->drawingState());

        if (state.layerStack == hw->getLayerStack()) {

            if (state.z >= minLayerZ && state.z <= maxLayerZ) {

                if (layer->isVisible()) {

                    if (filtering) layer->setFiltering(true);

                    layer->draw(hw);

                    if (filtering) layer->setFiltering(false);

                }

            }

        }

    }

    // compositionComplete is needed for older driver

    hw->compositionComplete();