Focus first invalid field of payment request editor

chrome/browser/ui/views/payments/validating_textfield.h

Index: chrome/browser/ui/views/payments/validating_textfield.h
diff --git a/chrome/browser/ui/views/payments/validating_textfield.h b/chrome/browser/ui/views/payments/validating_textfield.h
index ee0e1cf673277b814c636fc7390c6547c71b3f8e..69bcbc59b567f3ffc2754f5dc55c0b12c4b815ba 100644
--- a/chrome/browser/ui/views/payments/validating_textfield.h
+++ b/chrome/browser/ui/views/payments/validating_textfield.h
@@ -5,6 +5,8 @@
 #ifndef CHROME_BROWSER_UI_VIEWS_PAYMENTS_VALIDATING_TEXTFIELD_H_
 #define CHROME_BROWSER_UI_VIEWS_PAYMENTS_VALIDATING_TEXTFIELD_H_
 
+#include <memory>
+
 #include "base/macros.h"
 #include "chrome/browser/ui/views/payments/validation_delegate.h"
 #include "ui/views/controls/textfield/textfield.h"
@@ -26,6 +28,9 @@ class ValidatingTextfield : public views::Textfield {
   // Called when the textfield contents is changed. May do validation.
   void OnContentsChanged();
 
+  // Identifies whether the current content if valid or not.
+  bool IsValid();
+
  private:
   // Will call to the ValidationDelegate to validate the contents of the
   // textfield.