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diff --git a/chromium/ui/gfx/canvas_paint_win.h b/chromium/ui/gfx/canvas_paint_win.h
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+++ b/chromium/ui/gfx/canvas_paint_win.h
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+// Copyright (c) 2011 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 UI_GFX_CANVAS_PAINT_WIN_H_
+#define UI_GFX_CANVAS_PAINT_WIN_H_
+
+#include "skia/ext/platform_canvas.h"
+#include "ui/base/win/dpi.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/size.h"
+
+namespace gfx {
+
+// A class designed to help with WM_PAINT operations on Windows. It will create
+// the bitmap and canvas with the correct size and transform for the dirty rect.
+// The bitmap will be automatically painted to the screen on destruction.
+//
+// You MUST call isEmpty before painting to determine if anything needs
+// painting. Sometimes the dirty rect can actually be empty, and this makes
+// the bitmap functions we call unhappy. The caller should not paint in this
+// case.
+//
+// Therefore, all you need to do is:
+//   case WM_PAINT: {
+//     PAINTSTRUCT ps;
+//     HDC hdc = BeginPaint(hwnd, &ps);
+//     gfx::CanvasSkiaPaint canvas(hwnd, hdc, ps);
+//     if (!canvas.isEmpty()) {
+//       ... paint to the canvas ...
+//     }
+//     EndPaint(hwnd, &ps);
+//     return 0;
+//   }
+// Note: The created context is always inialized to (0, 0, 0, 0).
+class UI_EXPORT CanvasSkiaPaint : public Canvas {
+ public:
+  // This constructor assumes the canvas is opaque.
+  CanvasSkiaPaint(HWND hwnd, HDC dc, const PAINTSTRUCT& ps);
+  virtual ~CanvasSkiaPaint();
+
+  // Creates a CanvasSkiaPaint for the specified region that paints to the
+  // specified dc.
+  CanvasSkiaPaint(HDC dc, bool opaque, int x, int y, int w, int h);
+
+  // Returns the rectangle that is invalid.
+  virtual gfx::Rect GetInvalidRect() const;
+
+  // Returns true if the invalid region is empty. The caller should call this
+  // function to determine if anything needs painting.
+  bool is_empty() const {
+    return ps_.rcPaint.right - ps_.rcPaint.left == 0 ||
+           ps_.rcPaint.bottom - ps_.rcPaint.top == 0;
+  };
+
+  // Use to access the Windows painting parameters, especially useful for
+  // getting the bounding rect for painting: paintstruct().rcPaint
+  const PAINTSTRUCT& paint_struct() const { return ps_; }
+
+  // Returns the DC that will be painted to
+  HDC paint_dc() const { return paint_dc_; }
+
+ private:
+  void Init(bool opaque);
+
+  HWND hwnd_;
+  HDC paint_dc_;
+  PAINTSTRUCT ps_;
+
+  // Disallow copy and assign.
+  DISALLOW_COPY_AND_ASSIGN(CanvasSkiaPaint);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_CANVAS_PAINT_WIN_H_