Eliminate pinch drift by removing touch radius from span calculation

ui/events/gesture_detection/gesture_configuration.h

 // Copyright 2014 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_EVENTS_GESTURE_DETECTION_GESTURE_CONFIGURATION_H_
 #define UI_EVENTS_GESTURE_DETECTION_GESTURE_CONFIGURATION_H_
 
 #include "base/macros.h"
 #include "ui/events/gesture_detection/gesture_detection_export.h"
 #include "ui/events/gesture_detection/velocity_tracker.h"
 
 namespace ui {
 
 class GESTURE_DETECTION_EXPORT GestureConfiguration {
  public:
   // Sets the shared instance. This does not take ownership of |config|.
   static void SetInstance(GestureConfiguration* config);
   // Returns the singleton GestureConfiguration.
   static GestureConfiguration* GetInstance();
 
   // Ordered alphabetically ignoring underscores.
   float default_radius() const { return default_radius_; }
   void set_default_radius(float radius) {
     default_radius_ = radius;
-    min_scaling_touch_major_ = default_radius_ * 2;
     min_gesture_bounds_length_ = default_radius_;
   }
   bool double_tap_enabled() const { return double_tap_enabled_; }
   void set_double_tap_enabled(bool enabled) { double_tap_enabled_ = enabled; }
   int double_tap_timeout_in_ms() const { return double_tap_timeout_in_ms_; }
   bool fling_touchpad_tap_suppression_enabled() const {
     return fling_touchpad_tap_suppression_enabled_;
   }
   void set_fling_touchpad_tap_suppression_enabled(bool enabled) {
     fling_touchpad_tap_suppression_enabled_ = enabled;
@@ skipping 97 matching lines @@
   }
   void set_min_pinch_update_span_delta(float val) {
     min_pinch_update_span_delta_ = val;
   }
   float min_scaling_span_in_pixels() const {
     return min_scaling_span_in_pixels_;
   }
   void set_min_scaling_span_in_pixels(float val) {
     min_scaling_span_in_pixels_ = val;
   }
-  float min_scaling_touch_major() const { return min_scaling_touch_major_; }
   float min_swipe_velocity() const { return min_swipe_velocity_; }
   void set_min_swipe_velocity(float val) { min_swipe_velocity_ = val; }
   int scroll_debounce_interval_in_ms() const {
     return scroll_debounce_interval_in_ms_;
   }
   int set_scroll_debounce_interval_in_ms(int val) {
     return scroll_debounce_interval_in_ms_ = val;
   }
   int semi_long_press_time_in_ms() const {
     return semi_long_press_time_in_ms_;
@@ skipping 32 matching lines @@
 
   // The below configuration parameters are dependent on other parameters,
   // whose setter functions will setup these values as well, so we will not
   // provide public setter functions for them.
   void set_double_tap_timeout_in_ms(int val) {
     double_tap_timeout_in_ms_ = val;
   }
   void set_min_gesture_bounds_length(float val) {
     min_gesture_bounds_length_ = val;
   }
-  void set_min_scaling_touch_major(float val) {
-    min_scaling_touch_major_ = val;
-  }
   void set_span_slop(float val) { span_slop_ = val; }
 
  private:
   // Returns the platform specific instance. This is invoked if a specific
   // instance has not been set.
   static GestureConfiguration* GetPlatformSpecificInstance();
 
   // These are listed in alphabetical order ignoring underscores.
   // NOTE: Adding new configuration parameters requires initializing
   // corresponding entries in aura_test_base.cc's SetUp().
@@ skipping 37 matching lines @@
   float max_swipe_deviation_angle_;
   int max_time_between_double_click_in_ms_;
   int max_touch_down_duration_for_click_in_ms_;
   float max_touch_move_in_pixels_for_click_;
   float min_distance_for_pinch_scroll_in_pixels_;
   float min_fling_velocity_;
   float min_gesture_bounds_length_;
   // Only used with --compensate-for-unstable-pinch-zoom.
   float min_pinch_update_span_delta_;
   float min_scaling_span_in_pixels_;
-  float min_scaling_touch_major_;
   float min_swipe_velocity_;
   int scroll_debounce_interval_in_ms_;
   int semi_long_press_time_in_ms_;
   int show_press_delay_in_ms_;
   float span_slop_;
   bool swipe_enabled_;
 
   // TODO(davemoore): Move into chrome/browser/ui.
   int tab_scrub_activation_delay_in_ms_;
   bool two_finger_tap_enabled_;
   VelocityTracker::Strategy velocity_tracker_strategy_;
 
   DISALLOW_COPY_AND_ASSIGN(GestureConfiguration);
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_GESTURE_DETECTION_GESTURE_CONFIGURATION_H_