[Payment Request] Refactors the edit view controller

ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h

Index: ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h
diff --git a/ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h b/ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h
index bad55613614e1915cc860b490b6c9ec627058df6..cd36e8ebc7b4e4d3830200eb93426c5de4467e73 100644
--- a/ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h
+++ b/ios/chrome/browser/ui/payments/payment_request_edit_view_controller.h
@@ -14,19 +14,27 @@
 
 extern NSString* const kWarningMessageAccessibilityID;
 
+@class EditorField;
 @class PaymentRequestEditViewController;
 
+// Delegate protocol for PaymentRequestEditViewController.
+@protocol PaymentRequestEditViewControllerDelegate<NSObject>
+
+// Notifies the delegate that the user has selected |field|.
+- (void)paymentRequestEditViewController:
+            (PaymentRequestEditViewController*)controller
+                          didSelectField:(EditorField*)field;
+
+@end
+
 // Validator protocol for PaymentRequestEditViewController.
 @protocol PaymentRequestEditViewControllerValidator<NSObject>
 
-// Returns the validation error string for |value| which has the type
-// |autofillUIType|. |required| indicates whether this is a required field.
-// Returns nil if there are no validation errors.
+// Returns the validation error string for |field|. Returns nil if there are no
+// validation errors.
 - (NSString*)paymentRequestEditViewController:
                  (PaymentRequestEditViewController*)controller
-                                validateValue:(NSString*)value
-                               autofillUIType:(AutofillUIType)autofillUIType
-                                     required:(BOOL)required;
+                                validateField:(EditorField*)field;
 
 @end
 
@@ -40,6 +48,10 @@ extern NSString* const kWarningMessageAccessibilityID;
 @property(nonatomic, weak) id<PaymentRequestEditViewControllerDataSource>
     dataSource;
 
+// The delegate to be notified when the user selects an editor field.
+@property(nonatomic, weak) id<PaymentRequestEditViewControllerDelegate>
+    delegate;
+
 // The delegate to be called for validating the fields. By default, the
 // controller is the validator.
 @property(nonatomic, weak) id<PaymentRequestEditViewControllerValidator>