[Payments] Add support for required fields in editor validation

chrome/browser/ui/views/payments/credit_card_editor_view_controller.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/payments/credit_card_editor_view_controller.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/string16.h"
@@ skipping 15 matching lines @@
     PaymentRequest* request,
     PaymentRequestDialogView* dialog)
     : EditorViewController(request, dialog) {}
 
 CreditCardEditorViewController::~CreditCardEditorViewController() {}
 
 std::vector<EditorField> CreditCardEditorViewController::GetFieldDefinitions() {
   return std::vector<EditorField>{
       {autofill::CREDIT_CARD_NAME_FULL,
        l10n_util::GetStringUTF16(IDS_AUTOFILL_FIELD_LABEL_NAME_ON_CARD),
-       EditorField::LengthHint::HINT_LONG},
+       EditorField::LengthHint::HINT_LONG, true},
       {autofill::CREDIT_CARD_NUMBER,
        l10n_util::GetStringUTF16(IDS_AUTOFILL_FIELD_LABEL_CREDIT_CARD_NUMBER),
-       EditorField::LengthHint::HINT_LONG},
+       EditorField::LengthHint::HINT_LONG, true},
       {autofill::CREDIT_CARD_EXP_DATE_2_DIGIT_YEAR,
        l10n_util::GetStringUTF16(IDS_AUTOFILL_FIELD_LABEL_EXPIRATION_DATE),
-       EditorField::LengthHint::HINT_SHORT}};
+       EditorField::LengthHint::HINT_SHORT, true}};
 }
 
 bool CreditCardEditorViewController::ValidateModelAndSave() {
   autofill::CreditCard credit_card;
   credit_card.set_origin(autofill::kSettingsOrigin);
   for (const auto& field : text_fields()) {
     // ValidatingTextfield* is the key, EditorField is the value.
     DCHECK_EQ(autofill::CREDIT_CARD,
               autofill::AutofillType(field.second.type).group());
     if (field.first->invalid())
@@ skipping 19 matching lines @@
       field);
 }
 
 CreditCardEditorViewController::ValidationDelegate::ValidationDelegate(
     const EditorField& field)
     : field_(field) {}
 CreditCardEditorViewController::ValidationDelegate::~ValidationDelegate() {}
 
 bool CreditCardEditorViewController::ValidationDelegate::ValidateTextfield(
     views::Textfield* textfield) {
-  base::string16 error_message;
-  // TODO(mathp): Display |error_message| around |textfield|.
-  return autofill::IsValidForType(textfield->text(), field_.type,
-                                  &error_message);
+  if (!textfield->text().empty()) {
+    base::string16 error_message;
+    // TODO(mathp): Display |error_message| around |textfield|.
+    return autofill::IsValidForType(textfield->text(), field_.type,
+                                    &error_message);
+  }
+
+  // TODO(mathp): Display "required" error if applicable.
+  return !field_.required;
 }
 
 }  // namespace payments