Allow cert-popup for WebView guests.

components/constrained_window/constrained_window_views.h

Index: components/constrained_window/constrained_window_views.h
diff --git a/components/constrained_window/constrained_window_views.h b/components/constrained_window/constrained_window_views.h
index e8046767811a8127d51492eb0a3ade6c84efc3f0..f90751de8b9431029115a7c64b8f1d8a3c07c9c6 100644
--- a/components/constrained_window/constrained_window_views.h
+++ b/components/constrained_window/constrained_window_views.h
@@ -20,6 +20,7 @@ class WidgetDelegate;
 
 namespace web_modal {
 class ModalDialogHost;
+class PopupManager;
 class WebContentsModalDialogHost;
 }
 
@@ -41,6 +42,9 @@ void UpdateWidgetModalDialogPosition(
     views::Widget* widget,
     web_modal::ModalDialogHost* dialog_host);
 
+// Returns popup manager, if any, for WebContents.
+web_modal::PopupManager* PopupManager(content::WebContents* web_contents);
+
 // Calls CreateWebModalDialogViews, shows the dialog, and returns its widget.
 views::Widget* ShowWebModalDialogViews(
     views::WidgetDelegate* dialog,