Mac: Enable partial swap

ui/gfx/geometry/rect_f.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 UI_GFX_GEOMETRY_RECT_F_H_
 #define UI_GFX_GEOMETRY_RECT_F_H_
 
 #include <iosfwd>
 #include <string>
 
 #include "ui/gfx/geometry/point_f.h"
 #include "ui/gfx/geometry/size_f.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 
+#if defined(OS_MACOSX)
+typedef struct CGRect CGRect;
+#endif
+
 namespace gfx {
 
 class InsetsF;
 
 // A floating version of gfx::Rect.
 class GFX_EXPORT RectF {
  public:
   RectF() {}
   RectF(float width, float height) : size_(width, height) {}
   RectF(float x, float y, float width, float height)
       : origin_(x, y), size_(width, height) {}
   explicit RectF(const SizeF& size) : size_(size) {}
   RectF(const PointF& origin, const SizeF& size)
       : origin_(origin), size_(size) {}
 
+#if defined(OS_MACOSX)
+  explicit RectF(const CGRect& r);
+  // Construct an equivalent CoreGraphics object.
+  CGRect ToCGRect() const;
+#endif
+
   ~RectF() {}
 
   float x() const { return origin_.x(); }
   void set_x(float x) { origin_.set_x(x); }
 
   float y() const { return origin_.y(); }
   void set_y(float y) { origin_.set_y(y); }
 
   float width() const { return size_.width(); }
   void set_width(float width) { size_.set_width(width); }
@@ skipping 177 matching lines @@
 GFX_EXPORT RectF BoundingRect(const PointF& p1, const PointF& p2);
 
 // This is declared here for use in gtest-based unit tests but is defined in
 // the gfx_test_support target. Depend on that to use this in your unit test.
 // This should not be used in production code - call ToString() instead.
 void PrintTo(const RectF& rect, ::std::ostream* os);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GEOMETRY_RECT_F_H_