Use the window coordinate for the autofill bounds.

content/public/renderer/render_view.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_RENDERER_RENDER_VIEW_H_
 #define CONTENT_PUBLIC_RENDERER_RENDER_VIEW_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/strings/string16.h"
 #include "content/common/content_export.h"
 #include "content/public/common/top_controls_state.h"
 #include "ipc/ipc_sender.h"
 #include "third_party/WebKit/public/platform/WebPageVisibilityState.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace blink {
 class WebElement;
 class WebFrame;
 class WebLocalFrame;
 class WebNode;
 class WebString;
 class WebURLRequest;
 class WebView;
 struct WebContextMenuData;
+struct WebRect;
 }
 
 namespace gfx {
 class Point;
 class Size;
 }
 
 namespace content {
 
 class RenderFrame;
@@ skipping 79 matching lines @@
 
   // Returns |renderer_preferences_.accept_languages| value.
   virtual const std::string& GetAcceptLanguages() const = 0;
 
 #if defined(OS_ANDROID)
   virtual void UpdateTopControlsState(TopControlsState constraints,
                                       TopControlsState current,
                                       bool animate) = 0;
 #endif
 
+  // Converts the |rect| from viewport coordinates to window coordinates.

[bokan, 2015/12/03 20:49:20]

Could you add a bit of description here (or elsewhere if it makes more sense) on
what |viewport| and what |window| coordinates are?

[oshima, 2015/12/03 21:58:17]

I updated here for now, but I think we should update the chromium doc and point
to that instead once migration is completed.

+  virtual void convertViewportToWindow(blink::WebRect* rect) = 0;
+
  protected:
   ~RenderView() override {}
 
  private:
   // This interface should only be implemented inside content.
   friend class RenderViewImpl;
   RenderView() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_RENDER_VIEW_H_