ShellExecuteEx does not wait for process exit

[ysc3839]

WebView2Samples/SampleApps/WebView2APISample/AppWindow.cpp

Lines 74 to 81 in 8ec7de9

	if (ShellExecuteEx(&shExInfo))
	{
	returnCode = 0; // Install successfull
	}
	else
	{
	returnCode = 1; // Install failed
	}

When ShellExecuteEx returned, the installer is still installing.
A solution is to set SEE_MASK_NOCLOSEPROCESS flag, and then WaitForSingleObject(shExInfo.hProcess).

[ysc3839]

Ping @liminzhu @champnic

[champnic]

Thanks for catching this! I'll open a bug on our backlog.