Revert of Don't handle NaturalScroll in Chrome but pass it to CMT instead

ui/events/x/device_data_manager.cc

 // Copyright 2013 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/events/x/device_data_manager.h"
 
 #include <X11/extensions/XInput.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xlib.h>
 
@@ skipping 92 matching lines @@
 
 bool DeviceDataManager::IsTouchDataType(const int type) {
   return (type >= kTouchDataTypeStart) && (type <= kTouchDataTypeEnd);
 }
 
 DeviceDataManager* DeviceDataManager::GetInstance() {
   return Singleton<DeviceDataManager>::get();
 }
 
 DeviceDataManager::DeviceDataManager()
-    : xi_opcode_(-1),
+    : natural_scroll_enabled_(false),
+      xi_opcode_(-1),
       atom_cache_(gfx::GetXDisplay(), kCachedAtoms),
       button_map_count_(0) {
   CHECK(gfx::GetXDisplay());
   InitializeXInputInternal();
 
   // Make sure the sizes of enum and kCachedAtoms are aligned.
   CHECK(arraysize(kCachedAtoms) == static_cast<size_t>(DT_LAST_ENTRY) + 1);
   UpdateDeviceList(gfx::GetXDisplay());
   UpdateButtonMap();
 }
@@ skipping 45 matching lines @@
     xi_device_event_types_[XI_TouchUpdate] = true;
     xi_device_event_types_[XI_TouchEnd] = true;
   }
   return true;
 }
 
 bool DeviceDataManager::IsXInput2Available() const {
   return xi_opcode_ != -1;
 }
 
+float DeviceDataManager::GetNaturalScrollFactor(int sourceid) const {
+  // Natural scroll is touchpad-only.
+  if (sourceid >= kMaxDeviceNum || !touchpads_[sourceid])
+    return -1.0f;
+
+  return natural_scroll_enabled_ ? 1.0f : -1.0f;
+}
+
 void DeviceDataManager::UpdateDeviceList(Display* display) {
   cmt_devices_.reset();
   touchpads_.reset();
   for (int i = 0; i < kMaxDeviceNum; ++i) {
     valuator_count_[i] = 0;
     valuator_lookup_[i].clear();
     data_type_lookup_[i].clear();
     valuator_min_[i].clear();
     valuator_max_[i].clear();
     for (int j = 0; j < kMaxSlotNum; j++)
@@ skipping 255 matching lines @@
                                          float* x_offset, float* y_offset,
                                          float* x_offset_ordinal,
                                          float* y_offset_ordinal,
                                          int* finger_count) {
   *x_offset = 0;
   *y_offset = 0;
   *x_offset_ordinal = 0;
   *y_offset_ordinal = 0;
   *finger_count = 2;
 
+  XIDeviceEvent* xiev =
+      static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+  const float natural_scroll_factor = GetNaturalScrollFactor(xiev->sourceid);
   EventData data;
   GetEventRawData(*native_event, &data);
 
   if (data.find(DT_CMT_SCROLL_X) != data.end())
-    *x_offset = data[DT_CMT_SCROLL_X];
+    *x_offset = data[DT_CMT_SCROLL_X] * natural_scroll_factor;
   if (data.find(DT_CMT_SCROLL_Y) != data.end())
-    *y_offset = data[DT_CMT_SCROLL_Y];
+    *y_offset = data[DT_CMT_SCROLL_Y] * natural_scroll_factor;
   if (data.find(DT_CMT_ORDINAL_X) != data.end())
-    *x_offset_ordinal = data[DT_CMT_ORDINAL_X];
+    *x_offset_ordinal = data[DT_CMT_ORDINAL_X] * natural_scroll_factor;
   if (data.find(DT_CMT_ORDINAL_Y) != data.end())
-    *y_offset_ordinal = data[DT_CMT_ORDINAL_Y];
+    *y_offset_ordinal = data[DT_CMT_ORDINAL_Y] * natural_scroll_factor;
   if (data.find(DT_CMT_FINGER_COUNT) != data.end())
     *finger_count = static_cast<int>(data[DT_CMT_FINGER_COUNT]);
 }
 
 void DeviceDataManager::GetFlingData(const base::NativeEvent& native_event,
                                      float* vx, float* vy,
                                      float* vx_ordinal, float* vy_ordinal,
                                      bool* is_cancel) {
   *vx = 0;
   *vy = 0;
   *vx_ordinal = 0;
   *vy_ordinal = 0;
   *is_cancel = false;
 
+  XIDeviceEvent* xiev =
+      static_cast<XIDeviceEvent*>(native_event->xcookie.data);
+  const float natural_scroll_factor = GetNaturalScrollFactor(xiev->sourceid);
   EventData data;
   GetEventRawData(*native_event, &data);
 
   if (data.find(DT_CMT_FLING_X) != data.end())
-    *vx = data[DT_CMT_FLING_X];
+    *vx = data[DT_CMT_FLING_X] * natural_scroll_factor;
   if (data.find(DT_CMT_FLING_Y) != data.end())
-    *vy = data[DT_CMT_FLING_Y];
+    *vy = data[DT_CMT_FLING_Y] * natural_scroll_factor;
   if (data.find(DT_CMT_FLING_STATE) != data.end())
     *is_cancel = !!static_cast<unsigned int>(data[DT_CMT_FLING_STATE]);
   if (data.find(DT_CMT_ORDINAL_X) != data.end())
-    *vx_ordinal = data[DT_CMT_ORDINAL_X];
+    *vx_ordinal = data[DT_CMT_ORDINAL_X] * natural_scroll_factor;
   if (data.find(DT_CMT_ORDINAL_Y) != data.end())
-    *vy_ordinal = data[DT_CMT_ORDINAL_Y];
+    *vy_ordinal = data[DT_CMT_ORDINAL_Y] * natural_scroll_factor;
 }
 
 void DeviceDataManager::GetMetricsData(const base::NativeEvent& native_event,
                                        GestureMetricsType* type,
                                        float* data1, float* data2) {
   *type = kGestureMetricsTypeUnknown;
   *data1 = 0;
   *data2 = 0;
 
   EventData data;
@@ skipping 126 matching lines @@
   for (int j = start_valuator; j <= end_valuator; ++j) {
     valuator_lookup_[deviceid][j] = valuator_count_[deviceid];
     data_type_lookup_[deviceid][valuator_count_[deviceid]] = j;
     valuator_min_[deviceid][j] = min_value;
     valuator_max_[deviceid][j] = max_value;
     valuator_count_[deviceid]++;
   }
 }
 
 }  // namespace ui