Do not save passwords after back-navigation

components/autofill/content/renderer/password_autofill_agent.cc

 // 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.
 
 #include "components/autofill/content/renderer/password_autofill_agent.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 1064 matching lines @@
   }
 
   // Bug fix for crbug.com/368690. isProcessingUserGesture() is false when
   // the user is performing actions outside the page (e.g. typed url,
   // history navigation). We don't want to trigger saving in these cases.
   content::DocumentState* document_state =
       content::DocumentState::FromDataSource(
           navigated_frame->provisionalDataSource());
   content::NavigationState* navigation_state =
       document_state->navigation_state();
-  if (ui::PageTransitionIsWebTriggerable(navigation_state->transition_type()) &&
+  ui::PageTransition type = navigation_state->transition_type();
+  if (ui::PageTransitionIsWebTriggerable(type) &&
+      ui::PageTransitionIsNewNavigation(type) &&
       !blink::WebUserGestureIndicator::isProcessingUserGesture()) {
     // If onsubmit has been called, try and save that form.
     if (provisionally_saved_form_) {
       if (logger) {
         logger->LogPasswordForm(
             Logger::STRING_PROVISIONALLY_SAVED_FORM_FOR_FRAME,
             *provisionally_saved_form_);
       }
       Send(new AutofillHostMsg_PasswordFormSubmitted(
           routing_id(), *provisionally_saved_form_));
@@ skipping 283 matching lines @@
 void PasswordAutofillAgent::LegacyPasswordAutofillAgent::DidStopLoading() {
   agent_->DidStopLoading();
 }
 
 void PasswordAutofillAgent::LegacyPasswordAutofillAgent::
     DidStartProvisionalLoad(blink::WebLocalFrame* navigated_frame) {
   agent_->LegacyDidStartProvisionalLoad(navigated_frame);
 }
 
 }  // namespace autofill