Merge "Quick optimization for committing Layers"

    // clear the "changed" flags in current state

    mCurrentState.colorMatrixChanged = false;

    for (const auto& rootLayer : mDrawingState.layersSortedByZ) {

        rootLayer->commitChildList();

    }

    // TODO(b/163019109): See if this traversal is needed at all...

    if (!mOffscreenLayers.empty()) {

        mDrawingState.traverse([&](Layer* layer) {

        layer->commitChildList();

            // If the layer can be reached when traversing mDrawingState, then the layer is no

            // longer offscreen. Remove the layer from the offscreenLayer set.

            if (mOffscreenLayers.count(layer)) {

                mOffscreenLayers.erase(layer);

            }

        });

    }

    commitOffscreenLayers();

    mDrawingState.traverse([&](Layer* layer) { layer->updateMirrorInfo(); });