Bound the maximum touchscreen fling velocity.

ui/base/gestures/gesture_configuration.h

Index: ui/base/gestures/gesture_configuration.h
diff --git a/ui/base/gestures/gesture_configuration.h b/ui/base/gestures/gesture_configuration.h
index 256c5d280f9d0705bed5a7a3d46b31cd723d1ab4..2fc5470730be59055b7db35b2c44e44530e91690 100644
--- a/ui/base/gestures/gesture_configuration.h
+++ b/ui/base/gestures/gesture_configuration.h
@@ -149,6 +149,12 @@ class UI_EXPORT GestureConfiguration {
   static float fling_acceleration_curve_coefficients(int i) {
     return fling_acceleration_curve_coefficients_[i];
   }
+  static float fling_velocity_cap() {
+    return fling_velocity_cap_;
+  }
+  static void set_fling_velocity_cap(float val) {
+    fling_velocity_cap_ = val;
+  }
 
  private:
   // These are listed in alphabetical order ignoring underscores, to
@@ -187,6 +193,7 @@ class UI_EXPORT GestureConfiguration {
   static double rail_break_proportion_;
   static double rail_start_proportion_;
   static float fling_acceleration_curve_coefficients_[NumAccelParams];
+  static float fling_velocity_cap_;
 
   DISALLOW_COPY_AND_ASSIGN(GestureConfiguration);
 };