Trying to blindly fix WebTestCase unit test failure.

Navigate to about:blank initially, not "about:".

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73879 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/controls/webtest.cpp

@@ -80,7 +80,7 @@ void WebTestCase::setUp()
     m_browser = wxWebView::New(wxTheApp->GetTopWindow(), wxID_ANY);
 
     m_loaded = new EventCounter(m_browser, wxEVT_WEBVIEW_LOADED);
-    m_browser->LoadURL("about:");
+    m_browser->LoadURL("about:blank");
     ENSURE_LOADED;
 }