Merge pull request #279 from tomcatter/master

fix the field of class assignment error

com.unity.uiwidgets/Runtime/material/pickers/calendar_date_picker.cs

             D.assert(initialDate != null);
             D.assert(firstDate != null);
             D.assert(lastDate != null);
-            initialDate = utils.dateOnly(initialDate.Value);
-            firstDate = utils.dateOnly(firstDate.Value);
-            lastDate = utils.dateOnly(lastDate.Value);
+            this.initialDate = utils.dateOnly(initialDate.Value);
+            this.firstDate = utils.dateOnly(firstDate.Value);
+            this.lastDate = utils.dateOnly(lastDate.Value);
             D.assert(onDateChanged != null);
             D.assert(initialCalendarMode != null);