Do not convert from RectF to Rect by flooring.

ui/gfx/size_base.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_SIZE_BASE_H_
 #define UI_GFX_SIZE_BASE_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 23 matching lines @@
 
   Class Scale(float scale) const WARN_UNUSED_RESULT {
     return Scale(scale, scale);
   }
 
   Class Scale(float x_scale, float y_scale) const WARN_UNUSED_RESULT {
     return Class(static_cast<Type>(width_ * x_scale),
                  static_cast<Type>(height_ * y_scale));
   }
 
-  void set_width(Type width);
-  void set_height(Type height);
+  void set_width(Type width) { width_ = width; }
+  void set_height(Type height) { height_ = height; }
 
   bool operator==(const Class& s) const {
     return width_ == s.width_ && height_ == s.height_;
   }
 
   bool operator!=(const Class& s) const {
     return !(*this == s);
   }
 
   bool IsEmpty() const {
-    // Size doesn't allow negative dimensions, so testing for 0 is enough.
-    return (width_ == 0) || (height_ == 0);
+    return (width_ <= 0) || (height_ <= 0);
+  }
+
+  void ClampToNonNegative() {
+    if (width_ < 0)
+      width_ = 0;
+    if (height_ < 0)
+      height_ = 0;
   }
 
  protected:
-  SizeBase(Type width, Type height);
+  SizeBase(Type width, Type height)
+      : width_(width),
+        height_(height) {}
+
   // Destructor is intentionally made non virtual and protected.
   // Do not make this public.
-  ~SizeBase();
+  ~SizeBase() {}
 
  private:
   Type width_;
   Type height_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_SIZE_BASE_H_