update zh-cn/application-dev/windowmanager/system-window-stage.md.

Signed-off-by: N葛亚芳 <geyafang@huawei.com>

zh-cn/application-dev/windowmanager/system-window-stage.md

@@ -58,12 +58,11 @@
    当不再需要音量条窗口时，可根据具体实现逻辑，使用`hide`接口或`destroyWindow`接口对其进行隐藏或销毁。
 
 ```ts
-import ExtensionContext from '@ohos.application.ServiceExtensionAbility';
+import ExtensionContext from '@ohos.app.ability.ServiceExtensionAbility';
 import window from '@ohos.window';
 
 export default class ServiceExtensionAbility1 extends ExtensionContext {
     onCreate(want) {
-        console.log("[Demo] MainAbility onCreate")
         globalThis.abilityWant = want;
         // 1.创建音量条窗口。
         let windowClass = null;
@@ -151,7 +150,6 @@ import window from '@ohos.window';
 
 export default class ServiceExtensionAbility1 extends ExtensionContext {
     onCreate(want) {
-        console.log("[Demo] MainAbility onCreate")
         globalThis.abilityWant = want;
         // 创建音量条窗口。
         let windowClass = null;