Gesture recognition constants should all be stored in the GestureConfiguration object.

ui/aura/gestures/gesture_configuration.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_AURA_GESTURES_GESTURE_CONFIGURATION_H_
 #define UI_AURA_GESTURES_GESTURE_CONFIGURATION_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "ui/aura/aura_export.h"
 
 namespace aura {
 
 // TODO: Expand this design to support multiple OS configuration
 // approaches (windows, chrome, others).  This would turn into an
 // abstract base class.
 
 class AURA_EXPORT GestureConfiguration {
  public:
-  static double max_touch_down_duration_in_seconds_for_click() {
-    return max_touch_down_duration_in_seconds_for_click_;
+  // Ordered alphabetically ignoring underscores, to align with the
+  // associated list of prefs in gesture_prefs_aura.cc.
+  static double long_press_time_in_seconds() {
+    return long_press_time_in_seconds_;
   }
-  static void set_max_touch_down_duration_in_seconds_for_click(double val) {
-    max_touch_down_duration_in_seconds_for_click_ = val;
-  }
-  static double min_touch_down_duration_in_seconds_for_click() {
-    return min_touch_down_duration_in_seconds_for_click_;
-  }
-  static void set_min_touch_down_duration_in_seconds_for_click(double val) {
-    min_touch_down_duration_in_seconds_for_click_ = val;
+  static void set_long_press_time_in_seconds(double val) {
+    long_press_time_in_seconds_ = val;
   }
   static double max_seconds_between_double_click() {
     return max_seconds_between_double_click_;
   }
   static void set_max_seconds_between_double_click(double val) {
     max_seconds_between_double_click_ = val;
   }
+  static int max_separation_for_gesture_touches_in_pixels() {
+    return max_separation_for_gesture_touches_in_pixels_;
+  }
+  static void set_max_separation_for_gesture_touches_in_pixels(int val) {
+    max_separation_for_gesture_touches_in_pixels_ = val;
+  }
+  static double max_touch_down_duration_in_seconds_for_click() {
+    return max_touch_down_duration_in_seconds_for_click_;
+  }
+  static void set_max_touch_down_duration_in_seconds_for_click(double val) {
+    max_touch_down_duration_in_seconds_for_click_ = val;
+  }
   static double max_touch_move_in_pixels_for_click() {
     return max_touch_move_in_pixels_for_click_;
   }
   static void set_max_touch_move_in_pixels_for_click(double val) {
     max_touch_move_in_pixels_for_click_ = val;
   }
+  static double min_distance_for_pinch_scroll_in_pixels() {
+    return min_distance_for_pinch_scroll_in_pixels_;
+  }
+  static void set_min_distance_for_pinch_scroll_in_pixels(double val) {
+    min_distance_for_pinch_scroll_in_pixels_ = val;
+  }
   static double min_flick_speed_squared() {
     return min_flick_speed_squared_;
   }
   static void set_min_flick_speed_squared(double val) {
     min_flick_speed_squared_ = val;
   }
-  static double minimum_pinch_update_distance_in_pixels() {
-    return minimum_pinch_update_distance_in_pixels_;
+  static double min_pinch_update_distance_in_pixels() {
+    return min_pinch_update_distance_in_pixels_;
   }
-  static void set_minimum_pinch_update_distance_in_pixels(double val) {
-    minimum_pinch_update_distance_in_pixels_ = val;
+  static void set_min_pinch_update_distance_in_pixels(double val) {
+    min_pinch_update_distance_in_pixels_ = val;
   }
-  static double minimum_distance_for_pinch_scroll_in_pixels() {
-    return minimum_distance_for_pinch_scroll_in_pixels_;
+  static double min_rail_break_velocity() {
+    return min_rail_break_velocity_;
   }
-  static void set_minimum_distance_for_pinch_scroll_in_pixels(double val) {
-    minimum_distance_for_pinch_scroll_in_pixels_ = val;
+  static void set_min_rail_break_velocity(double val) {
+    min_rail_break_velocity_ = val;
   }
-
-  static int max_separation_for_gesture_touches_in_pixels() {
-    return max_separation_for_gesture_touches_in_pixels_;
+  static double min_scroll_delta_squared() {
+    return min_scroll_delta_squared_;
   }
-
-  static void set_max_separation_for_gesture_touches_in_pixels(int val) {
-    max_separation_for_gesture_touches_in_pixels_ = val;
+  static void set_min_scroll_delta_squared(double val) {
+    min_scroll_delta_squared_ = val;
+  }
+  static double min_touch_down_duration_in_seconds_for_click() {
+    return min_touch_down_duration_in_seconds_for_click_;
+  }
+  static void set_min_touch_down_duration_in_seconds_for_click(double val) {
+    min_touch_down_duration_in_seconds_for_click_ = val;
+  }
+  static int points_buffered_for_velocity() {
+    return points_buffered_for_velocity_;
+  }
+  static void set_points_buffered_for_velocity(int val) {
+    points_buffered_for_velocity_ = val;
+  }
+  static double rail_break_proportion() {
+    return rail_break_proportion_;
+  }
+  static void set_rail_break_proportion(double val) {
+    rail_break_proportion_ = val;
+  }
+  static double rail_start_proportion() {
+    return rail_start_proportion_;
+  }
+  static void set_rail_start_proportion(double val) {
+    rail_start_proportion_ = val;
   }
 
  private:
+  // These are listed in alphabetical order ignoring underscores, to
+  // align with the associated list of preferences in
+  // gesture_prefs_aura.cc. These two lists should be kept in sync.
+  static double long_press_time_in_seconds_;
+  static double max_seconds_between_double_click_;
+  static double max_separation_for_gesture_touches_in_pixels_;
   static double max_touch_down_duration_in_seconds_for_click_;
+  static double max_touch_move_in_pixels_for_click_;
+  static double min_distance_for_pinch_scroll_in_pixels_;
+  static double min_flick_speed_squared_;
+  static double min_pinch_update_distance_in_pixels_;
+  static double min_rail_break_velocity_;
+  static double min_scroll_delta_squared_;
   static double min_touch_down_duration_in_seconds_for_click_;
-  static double max_seconds_between_double_click_;
-  static double max_touch_move_in_pixels_for_click_;
-  static double min_flick_speed_squared_;
-  static double minimum_pinch_update_distance_in_pixels_;
-  static double minimum_distance_for_pinch_scroll_in_pixels_;
-  static int max_separation_for_gesture_touches_in_pixels_;
+  static int points_buffered_for_velocity_;
+  static double rail_break_proportion_;
+  static double rail_start_proportion_;
 
   DISALLOW_COPY_AND_ASSIGN(GestureConfiguration);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_GESTURES_GESTURE_CONFIGURATION_H_