HarmonyOS web渲染3d canvas模糊不清并且伴有闪屏

加上移动端的UA即可，参考下以下demo：

import { webview } from '@kit.ArkWeb';
@Entry
@Component
struct WebComponent {
  controller: webview.WebviewController = new webview.WebviewController();
  build() {
    Column() {
      Web({ src: '', controller: this.controller })
        .domStorageAccess(true)
        .onControllerAttached(()=>{
          this.controller.setCustomUserAgent('Mozilla/5.0 (xxx; VRD-AL10; HMSCore 6.3.0.331) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.88 HuaweiBrowser/12.0.4.1 Mobile Safari/537.36')
          this.controller.loadUrl('https://www.huawei.com/15248/html/index.html?scene_id=26929203')
        })
    }
  }
}