fix: item sizes getting 'disabled' resulting in gaps

Author: Akryum

packages/vue-virtual-scroller/src/components/DynamicScroller.vue

@@ -90,7 +90,6 @@ export default {
       vscrollData: {
         active: true,
         sizes: {},
-        validSizes: {},
         keyField: this.keyField,
         simpleArray: false,
       },
@@ -124,7 +123,7 @@ export default {
 
   watch: {
     items () {
-      this.forceUpdate(false)
+      this.forceUpdate()
     },
 
     simpleArray: {
@@ -196,9 +195,9 @@ export default {
       this.$emit('visible')
     },
 
-    forceUpdate (clear = true) {
+    forceUpdate (clear = false) {
       if (clear || this.simpleArray) {
-        this.vscrollData.validSizes = {}
+        this.vscrollData.sizes = {}
       }
       this.$_events.emit('vscroll:update', { force: true })
     },

packages/vue-virtual-scroller/src/components/DynamicScrollerItem.vue

@@ -63,7 +63,7 @@ export default {
     },
 
     size () {
-      return (this.vscrollData.validSizes[this.id] && this.vscrollData.sizes[this.id]) || 0
+      return this.vscrollData.sizes[this.id] || 0
     },
 
     finalActive () {
@@ -198,7 +198,6 @@ export default {
           this.vscrollParent.$_undefinedMap[this.id] = undefined
         }
         this.vscrollData.sizes[this.id] = size
-        this.vscrollData.validSizes[this.id] = true
         if (this.emitResize) this.$emit('resize', this.id)
       }
     },