Fix trigger repeat animation (#297)

* fix: submenu use rc-trigger repeat animation

* fix popupClassName judgement

src/SubMenu.tsx

@@ -561,18 +561,13 @@ export class SubMenu extends React.Component<SubMenuProps> {
       </div>
     );
 
-    // [Legacy] `getMotion` should call before `renderChildren`
-    const baseProps = this.getBaseProps();
-    const motion = this.getMotion(baseProps.mode, baseProps.visible);
-
     const children = this.renderChildren(props.children);
 
     const getPopupContainer = props.parentMenu.isRootMenu
       ? props.parentMenu.props.getPopupContainer
       : (triggerNode: HTMLElement) => triggerNode.parentNode;
     const popupPlacement = popupPlacementMap[props.mode];
     const popupAlign = props.popupOffset ? { offset: props.popupOffset } : {};
-    const popupClassName = props.mode === 'inline' ? '' : props.popupClassName;
     const {
       disabled,
       triggerSubMenuAction,
@@ -597,7 +592,10 @@ export class SubMenu extends React.Component<SubMenuProps> {
         {!isInlineMode && (
           <Trigger
             prefixCls={prefixCls}
-            popupClassName={`${prefixCls}-popup ${popupClassName}`}
+            popupClassName={classNames(`${prefixCls}-popup`, {
+              [props.popupClassName]:
+                props.mode !== 'inline' && props.popupClassName,
+            })}
             getPopupContainer={getPopupContainer}
             builtinPlacements={Object.assign({}, placements, builtinPlacements)}
             popupPlacement={popupPlacement}
@@ -609,7 +607,6 @@ export class SubMenu extends React.Component<SubMenuProps> {
             mouseLeaveDelay={subMenuCloseDelay}
             onPopupVisibleChange={this.onPopupVisibleChange}
             forceRender={forceSubMenuRender}
-            popupMotion={motion}
           >
             {title}
           </Trigger>