Fix form validation bubble positioning at hidpi.

content/browser/renderer_host/render_widget_host_view_aura.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_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 117 matching lines @@
   void Hide() override;
   bool IsShowing() override;
   gfx::Rect GetViewBounds() const override;
   void SetBackgroundColor(SkColor color) override;
   bool IsMouseLocked() override;
   gfx::Size GetVisibleViewportSize() const override;
   void SetInsets(const gfx::Insets& insets) override;
   void FocusedNodeTouched(const gfx::Point& location_dips_screen,
                           bool editable) override;
   void SetNeedsBeginFrames(bool needs_begin_frames) override;
+  float GetDeviceScaleFactor() const override;
 
   // Overridden from RenderWidgetHostViewBase:
   void InitAsPopup(RenderWidgetHostView* parent_host_view,
                    const gfx::Rect& pos) override;
   void InitAsFullscreen(RenderWidgetHostView* reference_host_view) override;
   void Focus() override;
   void UpdateCursor(const WebCursor& cursor) override;
   void SetIsLoading(bool is_loading) override;
   void RenderProcessGone(base::TerminationStatus status,
                          int error_code) override;
@@ skipping 467 matching lines @@
   std::unique_ptr<RenderWidgetHostViewEventHandler> event_handler_;
 
   base::WeakPtrFactory<RenderWidgetHostViewAura> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_