Removed potential memory leak in PasswordFormManager::OnRequestDone

components/password_manager/core/browser/password_form_manager.cc

 // Copyright (c) 2012 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 "components/password_manager/core/browser/password_form_manager.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram.h"
 #include "base/metrics/user_metrics.h"
@@ skipping 372 matching lines @@
     // distinguish between those forms and two different login forms on the
     // same domain. Filed http://crbug.com/294468 to look into this.
     if (logins_result[i]->type == PasswordForm::TYPE_GENERATED)
       credentials_to_keep.push_back(*logins_result[i]);
 
     if (current_score < best_score) {
       delete logins_result[i];
       continue;
     }
     if (current_score == best_score) {
+      PasswordForm* old_form = best_matches_[logins_result[i]->username_value];
+      if (old_form) {
+        if (preferred_match_ == old_form)
+          preferred_match_ = NULL;
+        delete old_form;
+      }
       best_matches_[logins_result[i]->username_value] = logins_result[i];
     } else if (current_score > best_score) {
       best_score = current_score;
       // This new login has a better score than all those up to this point
       // Note 'this' owns all the PasswordForms in best_matches_.
       STLDeleteValues(&best_matches_);
-      best_matches_.clear();

[Garrett Casto, 2014/07/22 21:06:44]

Was this intentional? I'm not sure why you don't want to clear best_matches_
here.

[Lukasz Jagielski, 2014/07/23 14:52:18]

I removed this, because STLDeleteValues does that already.

On 2014/07/22 21:06:44, Garrett Casto wrote:

       preferred_match_ = NULL;  // Don't delete, its owned by best_matches_.
       best_matches_[logins_result[i]->username_value] = logins_result[i];
     }
     preferred_match_ = logins_result[i]->preferred ? logins_result[i]
                                                    : preferred_match_;
   }
   // We're done matching now.
   state_ = POST_MATCHING_PHASE;
 
   if (best_score <= 0) {
@@ skipping 324 matching lines @@
     LogPasswordGenerationSubmissionEvent(PASSWORD_SUBMITTED);
 }
 
 void PasswordFormManager::SubmitFailed() {
   submit_result_ = kSubmitResultFailed;
   if (has_generated_password_)
     LogPasswordGenerationSubmissionEvent(PASSWORD_SUBMISSION_FAILED);
 }
 
 }  // namespace password_manager