Merge "Improve algorithm for deciding which dim layers to animate."

    boolean animateDimLayers() {

        int fullScreen = -1;

        int fullScreenAndDimming = -1;

        boolean result = false;

        for (int i = mState.size() - 1; i >= 0; i--) {

            DimLayer.DimLayerUser dimLayerUser = mState.keyAt(i);

            if (dimLayerUser.isFullscreen()) {

            DimLayer.DimLayerUser user = mState.keyAt(i);

            if (user.isFullscreen()) {

                fullScreen = i;

                if (mState.valueAt(i).continueDimming) {

                    break;

                    fullScreenAndDimming = i;

                }

            } else {

                // We always want to animate the non fullscreen windows, they don't share their

                // dim layers.

                result |= animateDimLayers(user);

            }

        }

        if (fullScreen != -1) {

            return animateDimLayers(mState.keyAt(fullScreen));

        } else {

            boolean result = false;

            for (int i = mState.size() - 1; i >= 0; i--) {

                result |= animateDimLayers(mState.keyAt(i));

        // For the shared, full screen dim layer, we prefer the animation that is causing it to

        // appear.

        if (fullScreenAndDimming != -1) {

            result |= animateDimLayers(mState.keyAt(fullScreenAndDimming));

        } else if (fullScreen != -1) {

            // If there is no animation for the full screen dim layer to appear, we can use any of

            // the animators that will cause it to disappear.

            result |= animateDimLayers(mState.keyAt(fullScreen));

        }

        return result;

    }

    }

    private boolean animateDimLayers(DimLayer.DimLayerUser dimLayerUser) {

        DimBehindState state = mState.get(dimLayerUser);