Re-implement the screensaver to use WebView instead of ExtensionDialogHost.

ui/views/test/test_views_delegate.cc

Index: ui/views/test/test_views_delegate.cc
diff --git a/ui/views/test/test_views_delegate.cc b/ui/views/test/test_views_delegate.cc
index a8fe51177da391d3e9d3ae3d49745f180bcf9d9e..21ae8ae1105c1ecef5eb42ed192ad07192f7057a 100644
--- a/ui/views/test/test_views_delegate.cc
+++ b/ui/views/test/test_views_delegate.cc
@@ -5,6 +5,7 @@
 #include "ui/views/test/test_views_delegate.h"
 
 #include "base/logging.h"
+#include "content/test/web_contents_tester.h"
 #include "ui/base/clipboard/clipboard.h"
 
 namespace views {
@@ -64,4 +65,11 @@ views::NativeWidgetHelperAura* TestViewsDelegate::CreateNativeWidgetHelper(
 }
 #endif
 
+content::WebContents* TestViewsDelegate::CreateWebContents(
+    content::BrowserContext* browser_context,
+    content::SiteInstance* site_instance) {
+  return content::WebContentsTester::CreateTestWebContents(browser_context,
+                                                           site_instance);
+}
+
 }  // namespace views