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

components/autofill/content/browser/content_autofill_driver.h

 // Copyright 2014 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_CONTENT_AUTOFILL_DRIVER_H_
 #define COMPONENTS_AUTOFILL_CONTENT_BROWSER_CONTENT_AUTOFILL_DRIVER_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 41 matching lines @@
   void PingRenderer() override;
   void PropagateAutofillPredictions(
       const std::vector<autofill::FormStructure*>& forms) override;
   void SendAutofillTypePredictionsToRenderer(
       const std::vector<FormStructure*>& forms) override;
   void RendererShouldAcceptDataListSuggestion(
       const base::string16& value) override;
   void RendererShouldClearFilledForm() override;
   void RendererShouldClearPreviewedForm() override;
   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;
 
   // Handles a message that came from the associated render frame.
   bool HandleMessage(const IPC::Message& message);
 
   // Called when the frame has navigated.
   void DidNavigateFrame(const content::LoadCommittedDetails& details,
                         const content::FrameNavigateParams& params);
 
   AutofillExternalDelegate* autofill_external_delegate() {
@@ skipping 24 matching lines @@
   // case where the Autofill native UI is enabled.
   AutofillExternalDelegate autofill_external_delegate_;
 
   // Driver for the interactive autocomplete dialog.
   RequestAutocompleteManager request_autocomplete_manager_;
 };
 
 }  // namespace autofill
 
 #endif  // COMPONENTS_AUTOFILL_CONTENT_BROWSER_CONTENT_AUTOFILL_DRIVER_H_