Fix NPE (issue 10708277)

    protected void getOverviewModePages(int[] range) {

        int count = mScreenOrder.size();

        int start = -1;

        int end = -1;

        //

        for (int i = 0; i < count; i++) {

            if (start < 0 && mScreenOrder.get(i) >= 0) {

                start = i;

            }

            if (start >=0 && mScreenOrder.get(i) >= 0) {

                end = i;

            }

        }

        range[0] = start;

        range[1] = end;

        int start = hasCustomContent() ? 1 : 0;

        int end = getChildCount() - 1;

        range[0] = Math.max(0, Math.min(start, getChildCount() - 1));

        range[1] = Math.max(0,  end);

     }

    protected void onStartReordering() {