Eliminate the use of autofill::REQUIRE_AUTOCOMPLETE [step 3 of 3].

components/autofill/core/common/autofill_constants.h

 // Copyright 2013 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.
 
 // Contains constants specific to the Autofill component.
 
 #ifndef COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_CONSTANTS_H_
 #define COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_CONSTANTS_H_
 
 #include <stddef.h>         // For size_t
 
 namespace autofill {
 
-// A bit field mask for form or form element requirements.
-// TODO(estade): remove after iOS no longer uses it. See crbug.com/459456
-enum RequirementsMask {
-  REQUIRE_NONE = 0,          // No requirements.
-  REQUIRE_AUTOCOMPLETE = 1,  // Require that autocomplete != off.
-};
-
 // Help URL for the Autofill dialog.
 extern const char kHelpURL[];
 
 // The number of fields required by Autofill.  Ideally we could send the forms
 // to Autofill no matter how many fields are in the forms; however, finding the
 // label for each field is a costly operation and we can't spare the cycles if
 // it's not necessary.
 extern const size_t kRequiredAutofillFields;
 
 // Options bitmask values for AutofillHostMsg_ShowPasswordSuggestions IPC
 enum ShowPasswordSuggestionsOptions {
   SHOW_ALL = 1 << 0 /* show all credentials, not just ones matching username */,
   IS_PASSWORD_FIELD = 1 << 1 /* input field is a password field */
 };
 
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_CONSTANTS_H_