Make gfx::Rect class operations consistently mutate the class they are called on.

ui/gfx/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.
@@ skipping 54 matching lines @@
   GdkRectangle ToGdkRectangle() const;
 #elif defined(OS_MACOSX)
   // Construct an equivalent CoreGraphics object.
   CGRect ToCGRect() const;
 #endif
 
   operator RectF() const {
     return RectF(origin().x(), origin().y(), size().width(), size().height());
   }
 
-  RectF Scale(float scale) const WARN_UNUSED_RESULT {
-    return Scale(scale, scale);
-  }
-
-  RectF Scale(float x_scale, float y_scale) const WARN_UNUSED_RESULT {
-    RectF original = *this;
-    return original.Scale(x_scale, y_scale);
-  }
-
   std::string ToString() const;
 };
 
 inline bool operator==(const Rect& lhs, const Rect& rhs) {
   return lhs.origin() == rhs.origin() && lhs.size() == rhs.size();
 }
 
 inline bool operator!=(const Rect& lhs, const Rect& rhs) {
   return !(lhs == rhs);
 }
 
 #if !defined(COMPILER_MSVC)
 extern template class RectBase<Rect, Point, Size, Insets, int>;
 #endif
 
 }  // namespace gfx
 
 #endif  // UI_GFX_RECT_H_