Add a regression test for the CardUnmaskPrompt.

chrome/browser/ui/autofill/card_unmask_prompt_controller.h

Index: chrome/browser/ui/autofill/card_unmask_prompt_controller.h
diff --git a/chrome/browser/ui/autofill/card_unmask_prompt_controller.h b/chrome/browser/ui/autofill/card_unmask_prompt_controller.h
index 8679e7a6a96be1346bbd0d0aff0ec4896b107f01..c6cf268c41e8ec75101e19c6a9e1a0ab02c75e2e 100644
--- a/chrome/browser/ui/autofill/card_unmask_prompt_controller.h
+++ b/chrome/browser/ui/autofill/card_unmask_prompt_controller.h
@@ -7,6 +7,10 @@
 
 #include "base/strings/string16.h"
 
+namespace base {
+class TimeDelta;
+}
+
 namespace content {
 class WebContents;
 }
@@ -32,6 +36,7 @@ class CardUnmaskPromptController {
   virtual bool InputCvcIsValid(const base::string16& input_text) const = 0;
   virtual bool InputExpirationIsValid(const base::string16& month,
                                       const base::string16& year) const = 0;
+  virtual base::TimeDelta GetSuccessMessageDuration() const = 0;
 };
 
 }  // namespace autofill