BI-138976 fix: 在init中计算

(cherry picked from commit 6f04b65783)

packages/fineui/src/base/list/virtualgrouplist.js

@@ -25,6 +25,7 @@ export class VirtualGroupList extends Widget {
     }
 
     init() {
+        this._calculateSummaryHeight();
         this.renderedIndex = -1;
     }
 
@@ -44,7 +45,7 @@ export class VirtualGroupList extends Widget {
                 },
                 {
                     type: VirtualGroup.xtype,
-                    height: rowHeight * items.length,
+                    height: this.summaryHeight,
                     ref: (ref) => {
                         this.container = ref;
                     },
@@ -77,7 +78,6 @@ export class VirtualGroupList extends Widget {
                 this.populate(newValue);
             })
             : o.items;
-        this._calculateSummaryHeight();
         this._populate();
         this.ticking = false;
         this.element.scroll(() => {