解决虚拟滚动配合keep-alive，active数据恢复后页面卡顿、内存飙升的问题

packages/table/src/methods.js

@@ -1680,7 +1680,7 @@ const Methods = {
   /**
    * 刷新滚动操作，手动同步滚动相关位置（对于某些特殊的操作，比如滚动条错位、固定列不同步）
    */
-  refreshScroll () {
+  refreshScroll (clearVirtualScroll = true) {
     const { lastScrollLeft, lastScrollTop } = this
     const { $refs } = this
     const { tableBody, leftBody, rightBody, tableFooter } = $refs
@@ -1690,7 +1690,7 @@ const Methods = {
     const tableFooterElem = tableFooter ? tableFooter.$el : null
     // 还原滚动条位置
     if (lastScrollLeft || lastScrollTop) {
-      return restoreScrollLocation(this, lastScrollLeft, lastScrollTop)
+      return restoreScrollLocation(this, lastScrollLeft, lastScrollTop, clearVirtualScroll)
     }
     // 重置
     setScrollTop(tableBodyElem, lastScrollTop)
@@ -4353,7 +4353,7 @@ const Methods = {
   /**
    * 手动清除滚动相关信息，还原到初始状态
    */
-  clearScroll () {
+  clearScroll (clearVirtualScroll = true) {
     const { $refs, scrollXStore, scrollYStore } = this
     const { tableBody, rightBody, tableFooter } = $refs
     const tableBodyElem = tableBody ? tableBody.$el : null
@@ -4371,8 +4371,10 @@ const Methods = {
       tableBodyElem.scrollTop = 0
       tableBodyElem.scrollLeft = 0
     }
-    scrollXStore.startIndex = 0
-    scrollYStore.startIndex = 0
+    if (clearVirtualScroll) {
+      scrollXStore.startIndex = 0
+      scrollYStore.startIndex = 0
+    }
     return this.$nextTick()
   },
   /**

packages/table/src/table.js

@@ -913,7 +913,7 @@ export default {
     this.preventEvent(null, 'mounted')
   },
   activated () {
-    this.recalculate().then(() => this.refreshScroll())
+    this.recalculate().then(() => this.refreshScroll(false))
     this.preventEvent(null, 'activated')
   },
   deactivated () {

packages/table/src/util.js

@@ -8,8 +8,8 @@ const lineOffsetSizes = {
   medium: 1
 }
 
-export function restoreScrollLocation (_vm, scrollLeft, scrollTop) {
-  return _vm.clearScroll().then(() => {
+export function restoreScrollLocation (_vm, scrollLeft, scrollTop, clearVirtualScroll = true) {
+  return _vm.clearScroll(clearVirtualScroll).then(() => {
     if (scrollLeft || scrollTop) {
       // 重置最后滚动状态
       _vm.lastScrollLeft = 0