横竖屏切换 布局异常~问题所在及解决方案

将Activity从竖屏页面切换至横屏页面，此时 弹出对话框布局异常，或者将app切换到后台，在切回前台时，退出横屏，此时会发现 竖屏界面 异常，部分字体偏大。
参考了#248 #44 #213 等issues都无法处理自己的问题

Start by reproducing the two flows described: rotating an Activity while a dialog is shown, and returning from the background before leaving landscape mode. Compare the behavior with the approaches discussed in issues #248, #44, and #213. Done means the dialog and portrait layout retain correct sizing after rotation and background/foreground transitions.

Escrita pelo modelo de indexação a partir do texto da issue.