requestLayout() improperly called by xxxxxxxxxxxxxxxxxxx ScrollViewContainer 問題

當scrollview內的內容更改大小時，Scrollview不會自行調整大小。效果是，當內容變小時，內容將留在原來的位置，當內容變大時，沒法看到。僅當ScrollView位於做爲MasterDetailPage的詳細信息的頁面內時纔會發生這種狀況。若是Detail是NavigationPage，則Scrollview能夠正常工做。

requestLayout() improperly called by md5b60ffeb829f638581ab2bb9b1a7f4f3f.ScrollViewContainer{67a6572 V.E...... ......ID 0,0-720,1136} during layout: running second layout pass

requestLayout() improperly called by md5270abb39e60627f0f200893b490a1ade.NavigationPageRenderer{1d5c6ce V.E...... ......I. 0,0-720,1136 #1} during second layout pass: posting in next frame

參考：

https://github.com/xamarin/Xamarin.Forms/issues/1332