[Password Manager] Offer to save when an iframe is detached

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 1012 matching lines @@
                               usernames_usage_, OTHER_POSSIBLE_USERNAMES_MAX);
     usernames_usage_ = NOTHING_TO_AUTOFILL;
   }
 }
 
 void PasswordAutofillAgent::DidStopLoading() {
   did_stop_loading_ = true;
 }
 
 void PasswordAutofillAgent::FrameDetached() {
+  // If a sub frame has been destroyed while the user was entering information
+  // into a password form, try to save the data. See https://crbug.com/450806
+  // for examples of sites that perform login using this technique.
+  if (render_frame()->GetWebFrame()->parent() &&
+      ProvisionallySavedPasswordIsValid()) {
+    Send(new AutofillHostMsg_InPageNavigation(routing_id(),
+                                              *provisionally_saved_form_));
+  }
   FrameClosing();
 }
 
 void PasswordAutofillAgent::WillSendSubmitEvent(
     const blink::WebFormElement& form) {
   // Forms submitted via XHR are not seen by WillSubmitForm if the default
   // onsubmit handler is overridden. Such submission first gets detected in
   // DidStartProvisionalLoad, which no longer knows about the particular form,
   // and uses the candidate stored in |provisionally_saved_form_|.
   //
@@ skipping 382 matching lines @@
 void PasswordAutofillAgent::LegacyPasswordAutofillAgent::DidStopLoading() {
   agent_->DidStopLoading();
 }
 
 void PasswordAutofillAgent::LegacyPasswordAutofillAgent::
     DidStartProvisionalLoad(blink::WebLocalFrame* navigated_frame) {
   agent_->LegacyDidStartProvisionalLoad(navigated_frame);
 }
 
 }  // namespace autofill