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

components/password_manager/core/browser/password_manager_driver.h

Index: components/password_manager/core/browser/password_manager_driver.h
diff --git a/components/password_manager/core/browser/password_manager_driver.h b/components/password_manager/core/browser/password_manager_driver.h
index 9a634484edcd2e4f80e9cbb68faf3a409377eb8a..5d8b0f277d7776faed536bb3f33cd7f8074acd25 100644
--- a/components/password_manager/core/browser/password_manager_driver.h
+++ b/components/password_manager/core/browser/password_manager_driver.h
@@ -63,7 +63,8 @@ class PasswordManagerDriver
   // Tells the driver to preview filling form with the |username| and
   // |password|.
   virtual void PreviewSuggestion(const base::string16& username,
-                                 const base::string16& password) = 0;
+                                 const base::string16& password,
+                                 size_t match_start) = 0;
 
   // Tells the driver to clear previewed password and username fields.
   virtual void ClearPreviewedForm() = 0;