Install WebView2 failed

[glen0125]

If WebView2 is not installed on the system, such as on Win7 and some older versions of Win10, an error message indicating installation failure of WebView2 will pop up during the installation process.
Versin：Windows 1.0.1.107

[ck98734]

Detect whether webview2 exists, if not installed

[ck98734]

202acb5

[Xiongdan007]

win117 test failed.