Android 10.0 SystemUI 修改下拉通知栏每条通知的间距

在原生SystemUI中下拉状态栏的每条通知之间的间距是一条横线分开的，显得不太美观，所以要进行定制化改动
首选看源码 NotificationChildrenContainer.java

路径为：frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/notification/stack/NotificationChildrenContainer.java

  /**
     * Add a child notification to this view.
     *
     * @param row the row to add
     * @param childIndex the index to add it at, if -1 it will be added at the end
     */
    public void addNotification(ExpandableNotificationRow row, int childIndex) {
   
    
    
        int newIndex = childIndex < 0 ? mChildren.size