Fixed change items count less than before case padding error. #15

Author: tangbc

index.js

@@ -174,9 +174,11 @@
                     delta.start = 0
                 }
 
+                var hasPadding = slots.length > delta.keeps
+
                 delta.total = slots.length
-                delta.paddingTop = this.size * delta.start
-                delta.allPadding = this.size * (slots.length - delta.keeps)
+                delta.paddingTop = this.size * (hasPadding ? delta.start : 0)
+                delta.allPadding = this.size * (hasPadding ? slots.length - delta.keeps : 0)
 
                 return slots.filter(function (slot, index) {
                     return index >= delta.start && index <= delta.end