Allow cert-popup for WebView guests.

chrome/browser/ui/views/certificate_selector.h

Index: chrome/browser/ui/views/certificate_selector.h
diff --git a/chrome/browser/ui/views/certificate_selector.h b/chrome/browser/ui/views/certificate_selector.h
index 0f4d246d59ff58922a033448177a82a004102eea..2c1a63a1780ea0725ced7a8c2f8be629c64bc1cc 100644
--- a/chrome/browser/ui/views/certificate_selector.h
+++ b/chrome/browser/ui/views/certificate_selector.h
@@ -34,6 +34,11 @@ class CertificateSelector : public views::DialogDelegateView,
                             public views::ButtonListener,
                             public views::TableViewObserver {
  public:
+  // Indicates if the dialog can be successfully shown.
+  // TODO(davidben): Remove this when the certificate selector prompt is moved
+  // to the WebContentsDelegate. https://crbug.com/456255.
+  static bool CanShow(content::WebContents* web_contents);
+
   class CertificateTableModel;
 
   // |web_contents| must not be null.