Port of Android platform gesture detection code to C++

ui/events/gesture_detection/gesture_config_helper_android.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/gesture_config_helper.h"
+
+#include "ui/gfx/android/view_configuration.h"
+#include "ui/gfx/screen.h"
+
+using gfx::ViewConfiguration;
+
+namespace ui {
+
+// TODO(jdduke): Adopt GestureConfiguration on Android, crbug/339203.
+
+GestureDetector::Config DefaultGestureDetectorConfig() {
+  GestureDetector::Config config;
+
+  config.longpress_timeout = base::TimeDelta::FromMilliseconds(
+      ViewConfiguration::GetLongPressTimeoutInMs());
+  config.tap_timeout = base::TimeDelta::FromMilliseconds(
+      ViewConfiguration::GetTapTimeoutInMs());
+  config.double_tap_timeout = base::TimeDelta::FromMilliseconds(
+      ViewConfiguration::GetDoubleTapTimeoutInMs());
+
+  config.scaled_touch_slop = ViewConfiguration::GetTouchSlopInPixels();
+  config.scaled_double_tap_slop = ViewConfiguration::GetDoubleTapSlopInPixels();
+  config.scaled_minimum_fling_velocity =
+      ViewConfiguration::GetMinimumFlingVelocityInPixelsPerSecond();
+  config.scaled_maximum_fling_velocity =
+      ViewConfiguration::GetMaximumFlingVelocityInPixelsPerSecond();
+
+  return config;
+}
+
+ScaleGestureDetector::Config DefaultScaleGestureDetectorConfig() {
+  ScaleGestureDetector::Config config;
+
+  config.gesture_detector_config = DefaultGestureDetectorConfig();
+  // TODO(jdduke): Enable "quick scale" on the ScaleGestureDetector, and remove
+  // corresponding double tap drag zoom code from GestureProvider, crbug/331092.
+  config.quick_scale_enabled = false;
+  config.min_scaling_touch_major =
+      ViewConfiguration::GetMinScalingTouchMajorInPixels();
+  config.min_scaling_span = ViewConfiguration::GetMinScalingSpanInPixels();
+
+  return config;
+}
+
+SnapScrollController::Config DefaultSnapScrollControllerConfig() {
+  SnapScrollController::Config config;
+
+  const gfx::Display& display =
+      gfx::Screen::GetNativeScreen()->GetPrimaryDisplay();
+
+  config.screen_width_pixels = display.GetSizeInPixel().width();
+  config.screen_height_pixels = display.GetSizeInPixel().height();
+  config.device_scale_factor = display.device_scale_factor();
+
+  return config;
+}
+
+GestureProvider::Config DefaultGestureProviderConfig() {
+  GestureProvider::Config config;
+  config.gesture_detector_config = DefaultGestureDetectorConfig();
+  config.scale_gesture_detector_config = DefaultScaleGestureDetectorConfig();
+  config.snap_scroll_controller_config = DefaultSnapScrollControllerConfig();
+  return config;
+}
+
+}  // namespace ui