HarmonyOS WebView 圆角设置失效

Web组件在某些场景下我们不会全屏显示，且给左上角右上角设置圆角不会生效。可以用下面的demo来进行验证。

import web_webview from '@ohos.web.webview';
import business_error from '@ohos.base';

@Entry
@Component
struct Page2 {
  controller: web_webview.WebviewController = new web_webview.WebviewController();
  @State progress: number = 0;
  @State src: string = 'https://www.huawei.com/u/bmmain/helpsale/evaluate?random=1000&channel=BM_0933&needHideHead=3&cateId=101&type=B&plainSceneId=B2COld2New&modelId=125986&brandId=10532&modelName=%E5%8D%8E%E4%B8%BA%20Mate%2060%20Pro&skip2NextUrl=https%3A%2F%2Fm.zhuanzhuan.com%2Fzlj%2Fold_for_new_service_h5%2Fvaluation%3FneedHideHead%3D3%26needNewWebview%3D1%26serviceIds%3D%26productId%3D1779861808894005248%26metric%3D%26from%3Dc2b%26isUserEval%3D1';
  ;

  build() {
    Column() {
      Row().height('30%')
      Stack() {
        Web({ src: this.src, controller: this.controller })
          .borderRadius({ topLeft: 100, topRight: 100, bottomLeft: 0, bottomRight: 0 })
          .javaScriptAccess(true)
          .domStorageAccess(true)
          .onProgressChange((event) => {
            this.progress = event?.newProgress || 0;
            // console.log(`progress: ${this.progress}`);
          })
          .height('100%')
        Column({ space: 20 }) {
          Text(`progress: ${this.progress}`).fontSize(30).fontColor(Color.Black)
          Button('loadUrl')
            .onClick(() => {
              try {
                this.controller.setCustomUserAgent("zzVersion/8.18.20 zzT/16 zzDevice/1_44.0_3.0 zzApp/58ZhuanZhuan");
                const customUa = this.controller.getCustomUserAgent();
                const ua = this.controller.getUserAgent();
                console.log(`customUa: ${customUa}, ua: ${ua}`);
              } catch (error) {
                let e: business_error.BusinessError = error as business_error.BusinessError;
                console.error(`ErrorCode: ${e.code},  Message: ${e.message}`);
              }
            })
        }
      }
      .height('70%')
    }.backgroundColor(Color.Black)
  }
}