Postpone rail application for touch scrolling - chrome side.

ui/events/gesture_detection/snap_scroll_controller.cc

 // 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.
 
 #include "ui/events/gesture_detection/snap_scroll_controller.h"
 
 #include <cmath>
 
 #include "ui/events/gesture_detection/motion_event.h"
 
@@ skipping 73 matching lines @@
       down_position_ = gfx::PointF();
       accumulated_distance_ = gfx::Vector2dF();
       break;
     default:
       break;
   }
 }
 
 void SnapScrollController::UpdateSnapScrollMode(float distance_x,
                                                 float distance_y) {
-  if (!IsSnappingScrolls())
+  if (mode_ != SNAP_VERT && mode_ != SNAP_HORIZ)
     return;
 
   accumulated_distance_ +=
       gfx::Vector2dF(std::abs(distance_x), std::abs(distance_y));
   if (mode_ == SNAP_HORIZ) {
     if (accumulated_distance_.y() > channel_distance_)
       mode_ = SNAP_NONE;
     else if (accumulated_distance_.x() > channel_distance_)
       accumulated_distance_ = gfx::Vector2dF();
   } else if (mode_ == SNAP_VERT) {
     if (accumulated_distance_.x() > channel_distance_)
       mode_ = SNAP_NONE;
     else if (accumulated_distance_.y() > channel_distance_)
       accumulated_distance_ = gfx::Vector2dF();
   }
 }
 
 bool SnapScrollController::IsSnapVertical() const {
-  return mode_ == SNAP_VERT;
+  return ScrollRailState() == GestureEventDetails::ScrollRailState::Vertical;
 }
 
 bool SnapScrollController::IsSnapHorizontal() const {
-  return mode_ == SNAP_HORIZ;
+  return ScrollRailState() == GestureEventDetails::ScrollRailState::Horizontal;
 }
 
 bool SnapScrollController::IsSnappingScrolls() const {
-  return IsSnapHorizontal() || IsSnapVertical();
+  return ScrollRailState() != GestureEventDetails::ScrollRailState::Free;
+}
+
+
+GestureEventDetails::ScrollRailState SnapScrollController::ScrollRailState()
+    const {
+  if (mode_ == SNAP_VERT)
+    return GestureEventDetails::ScrollRailState::Vertical;
+  if (mode_ == SNAP_HORIZ)
+    return GestureEventDetails::ScrollRailState::Horizontal;
+  return GestureEventDetails::ScrollRailState::Free;
 }
 
 }  // namespace ui