Use the window coordinate for the autofill bounds.

components/autofill/content/renderer/password_generation_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_generation_agent.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "components/autofill/content/common/autofill_messages.h"
@@ skipping 393 matching lines @@
     // Password isn't generated and there are fewer than kMaximumOfferSize
     // characters typed, so keep offering the password. Note this function
     // will just keep the previous popup if one is already showing.
     ShowGenerationPopup();
   }
 
   return true;
 }
 
 void PasswordGenerationAgent::ShowGenerationPopup() {
+  blink::WebRect bounding_box_in_window =
+      generation_element_.boundsInViewport();
+  render_frame()->GetRenderView()->convertViewportToWindow(
+      &bounding_box_in_window);
+
   Send(new AutofillHostMsg_ShowPasswordGenerationPopup(
-      routing_id(), gfx::RectF(generation_element_.boundsInViewport()),
+      routing_id(), gfx::RectF(bounding_box_in_window),
       generation_element_.maxLength(), *generation_form_data_->form));
 
   generation_popup_shown_ = true;
 }
 
 void PasswordGenerationAgent::ShowEditingPopup() {
+  blink::WebRect bounding_box_in_window =
+      generation_element_.boundsInViewport();
+  render_frame()->GetRenderView()->convertViewportToWindow(
+      &bounding_box_in_window);
   Send(new AutofillHostMsg_ShowPasswordEditingPopup(
-      routing_id(), gfx::RectF(generation_element_.boundsInViewport()),
+      routing_id(), gfx::RectF(bounding_box_in_window),
       *generation_form_data_->form));
-
   editing_popup_shown_ = true;
 }
 
 void PasswordGenerationAgent::HidePopup() {
   Send(new AutofillHostMsg_HidePasswordGenerationPopup(routing_id()));
 }
 
 }  // namespace autofill