Provide gtest printers for ui/gfx geometry types

ui/gfx/geometry/rect.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.
 
 // Defines a simple integer rectangle class.  The containment semantics
 // are array-like; that is, the coordinate (x, y) is considered to be
 // contained by the rectangle, but the coordinate (x + width, y) is not.
 // The class will happily let you create malformed rectangles (that is,
 // rectangles with negative width and/or height), but there will be assertions
 // in the operations (such as Contains()) to complain in this case.
 
 #ifndef UI_GFX_GEOMETRY_RECT_H_
 #define UI_GFX_GEOMETRY_RECT_H_
 
 #include <cmath>
+#include <iosfwd>
 #include <string>
 
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect_base.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/vector2d.h"
 
 #if defined(OS_WIN)
 typedef struct tagRECT RECT;
@@ skipping 101 matching lines @@
 }
 
 inline Rect ScaleToEnclosedRect(const Rect& rect, float scale) {
   return ScaleToEnclosedRect(rect, scale, scale);
 }
 
 #if !defined(COMPILER_MSVC)
 extern template class RectBase<Rect, Point, Size, Insets, Vector2d, int>;
 #endif
 
+// 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 Rect& rect, ::std::ostream* os);
+
 }  // namespace gfx
 
 #endif  // UI_GFX_GEOMETRY_RECT_H_