Use a bezier timing function for the overview mode animation

ui/gfx/animation/tween.cc

 // 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.
 
 #include "ui/gfx/animation/tween.h"
 
 #include <math.h>
 
 #if defined(OS_WIN)
 #include <float.h>
 #endif
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
+#include "ui/gfx/geometry/cubic_bezier.h"
 #include "ui/gfx/safe_integer_conversions.h"
 
 namespace gfx {
 
 // static
 double Tween::CalculateValue(Tween::Type type, double state) {
   DCHECK_GE(state, 0);
   DCHECK_LE(state, 1);
 
   switch (type) {
     case EASE_IN:
       return pow(state, 2);
 
     case EASE_IN_2:
       return pow(state, 4);
 
+    case EASE_IN_BEZIER:
+      return gfx::CubicBezier(.4, 0, 1, .2).Solve(state);
+
     case EASE_IN_OUT:
       if (state < 0.5)
         return pow(state * 2, 2) / 2.0;
       return 1.0 - (pow((state - 1.0) * 2, 2) / 2.0);
 
     case FAST_IN_OUT:
       return (pow(state - 0.5, 3) + 0.125) / 0.25;
 
     case LINEAR:
       return state;
 
     case EASE_OUT_SNAP:
       state = 0.95 * (1.0 - pow(1.0 - state, 2));
       return state;
 
     case EASE_OUT:
       return 1.0 - pow(1.0 - state, 2);
 
+    case EASE_OUT_BEZIER:
+      return gfx::CubicBezier(.4, 0, .2, 1).Solve(state);
+
     case SMOOTH_IN_OUT:
       return sin(state);
 
     case ZERO:
       return 0;
   }
 
   NOTREACHED();
   return state;
 }
@@ skipping 103 matching lines @@
   if (value <= 0.0)
     return start_transform;
 
   gfx::Transform to_return = end_transform;
   to_return.Blend(start_transform, value);
 
   return to_return;
 }
 
 }  // namespace gfx