Fix bug # 1715974. Layout document view after loading the PDF, mainly to fix the scaling when the PDF auto-scales. 
Fix bug # 1715974. Layout document view after loading the PDF, mainly to fix the scaling when the PDF auto-scales. 

JackieXie168/skim,JackieXie168/skim,JackieXie168/skim,JackieXie168/skim,JackieXie168/skim