Define accelerated steps time function.

ui/gfx/geometry/steps.h

Index: ui/gfx/geometry/steps.h
diff --git a/ui/gfx/geometry/steps.h b/ui/gfx/geometry/steps.h
new file mode 100644
index 0000000000000000000000000000000000000000..f831b3f9a3171426a5b6047ee8fd8b330dd46d9e
--- /dev/null
+++ b/ui/gfx/geometry/steps.h
@@ -0,0 +1,34 @@
+// Copyright 2014 Samsung. All rights reserved.

[ajuma, 2014/02/24 21:11:16]

I believe this should be "The Chromium Authors" (see
http://www.chromium.org/developers/coding-style#TOC-File-headers). Note also
that you'll need to sign the CLA (see
http://dev.chromium.org/developers/contributing-code/external-contributor-che...)
and add yourself to the AUTHORS file.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_GFX_GEOMETRY_STEPS_H_
+#define UI_GFX_GEOMETRY_STEPS_H_
+
+#include "base/macros.h"
+#include "ui/gfx/gfx_export.h"
+
+namespace gfx {
+
+class GFX_EXPORT Steps {
+ public:
+  Steps(int steps, bool steps_at_start);
+  ~Steps();
+
+  // Returns y at the given x.
+  double Solve(double x) const;
+
+  // Sets |min| and |max| to the bezier's minimum and maximium y values in the

[ajuma, 2014/02/24 21:11:16]

s/bezier/step function/

+  // interval [0, 1].
+  void Range(double* min, double* max) const;
+
+ private:
+  int steps_;
+  bool steps_at_start_;
+
+  DISALLOW_ASSIGN(Steps);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_GEOMETRY_STEPS_H_