[Autofill/Autocomplete Feature] Substring matching instead of prefix matching.

components/autofill/ios/browser/autofill_driver_ios.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.
 
 #ifndef COMPONENTS_AUTOFILL_CONTENT_BROWSER_AUTOFILL_DRIVER_IOS_H_
 #define COMPONENTS_AUTOFILL_CONTENT_BROWSER_AUTOFILL_DRIVER_IOS_H_
 
 #include <string>
 
 #include "components/autofill/core/browser/autofill_client.h"
@@ skipping 38 matching lines @@
       const std::vector<FormStructure*>& forms) override;
   void RendererShouldClearFilledForm() override;
   void RendererShouldClearPreviewedForm() override;
   void RendererShouldAcceptDataListSuggestion(
       const base::string16& value) override;
   base::SequencedWorkerPool* GetBlockingPool() override;
 
   AutofillManager* autofill_manager() { return &autofill_manager_; }
 
   void RendererShouldFillFieldWithValue(const base::string16& value) override;
-  void RendererShouldPreviewFieldWithValue(
-      const base::string16& value) override;
+  void RendererShouldPreviewFieldWithValue(const base::string16& value,
+                                           size_t match_start) override;
   void PopupHidden() override;
 
  private:
   AutofillDriverIOS(
       web::WebState* web_state,
       AutofillClient* client,
       id<AutofillDriverIOSBridge> bridge,
       const std::string& app_locale,
       AutofillManager::AutofillDownloadManagerState enable_download_manager);
   ~AutofillDriverIOS() override;
 
   // The WebState with which this object is associated.
   web::WebState* web_state_;
 
   // AutofillDriverIOSBridge instance that is passed in.
   id<AutofillDriverIOSBridge> bridge_;
 
   // AutofillManager instance via which this object drives the shared Autofill
   // code.
   AutofillManager autofill_manager_;
   // AutofillExternalDelegate instance that is passed to the AutofillManager.
   AutofillExternalDelegate autofill_external_delegate_;
 };
 
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_CONTENT_BROWSER_AUTOFILL_DRIVER_IOS_H_