chrome/browser/ui/gesture_prefs_observer_factory_aura.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/ui/gesture_prefs_observer_factory_aura.h"
   6
   7 #include <vector>
   8
   9 #include "base/bind.h"
  10 #include "base/bind_helpers.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/prefs/pref_change_registrar.h"
  13 #include "base/prefs/pref_service.h"
  14 #include "chrome/browser/chrome_notification_types.h"
  15 #include "chrome/browser/profiles/incognito_helpers.h"
  16 #include "chrome/browser/profiles/profile.h"
  17 #include "chrome/common/pref_names.h"
  18 #include "components/browser_context_keyed_service/browser_context_dependency_manager.h"
  19 #include "components/user_prefs/pref_registry_syncable.h"
  20 #include "content/public/browser/notification_observer.h"
  21 #include "content/public/browser/notification_service.h"
  22 #include "content/public/browser/overscroll_configuration.h"
  23 #include "content/public/common/renderer_preferences.h"
  24 #include "ui/events/gestures/gesture_configuration.h"
  25
  26 using ui::GestureConfiguration;
  27
  28 namespace {
  29
  30 // TODO(tdresser): Remove this deprecated pref. See crbug.com/339486.
  31 const char kMinScrollSuccessiveVelocityEvents[] =
  32     "gesture.min_scroll_successive_velocity_events";
  33
  34 struct OverscrollPref {
  35   const char* pref_name;
  36   content::OverscrollConfig config;
  37 };
  38
  39 const std::vector<OverscrollPref>& GetOverscrollPrefs() {
  40   CR_DEFINE_STATIC_LOCAL(std::vector<OverscrollPref>, overscroll_prefs, ());
  41   if (overscroll_prefs.empty()) {
  42     using namespace content;
  43     const OverscrollPref kOverscrollPrefs[] = {
  44       { prefs::kOverscrollHorizontalThresholdComplete,
  45         OVERSCROLL_CONFIG_HORIZ_THRESHOLD_COMPLETE },
  46       { prefs::kOverscrollVerticalThresholdComplete,
  47         OVERSCROLL_CONFIG_VERT_THRESHOLD_COMPLETE },
  48       { prefs::kOverscrollMinimumThresholdStart,
  49         OVERSCROLL_CONFIG_HORIZ_THRESHOLD_START_TOUCHSCREEN },
  50       { prefs::kOverscrollMinimumThresholdStartTouchpad,
  51         OVERSCROLL_CONFIG_HORIZ_THRESHOLD_START_TOUCHPAD },
  52       { prefs::kOverscrollVerticalThresholdStart,
  53         OVERSCROLL_CONFIG_VERT_THRESHOLD_START },
  54       { prefs::kOverscrollHorizontalResistThreshold,
  55         OVERSCROLL_CONFIG_HORIZ_RESIST_AFTER },
  56       { prefs::kOverscrollVerticalResistThreshold,
  57         OVERSCROLL_CONFIG_VERT_RESIST_AFTER },
  58     };
  59     overscroll_prefs.assign(kOverscrollPrefs,
  60                             kOverscrollPrefs + arraysize(kOverscrollPrefs));
  61   }
  62   return overscroll_prefs;
  63 }
  64
  65 // This class manages gesture configuration preferences.
  66 class GesturePrefsObserver : public BrowserContextKeyedService {
  67  public:
  68   explicit GesturePrefsObserver(PrefService* prefs);
  69   virtual ~GesturePrefsObserver();
  70
  71   // BrowserContextKeyedService implementation.
  72   virtual void Shutdown() OVERRIDE;
  73
  74  private:
  75   // Notification callback invoked when browser-side preferences
  76   // are updated and need to be pushed into ui::GesturePreferences.
  77   void Update();
  78
  79   // Notification callback invoked when the fling deacceleration
  80   // gesture preferences are changed from chrome://gesture.
  81   // Broadcasts the changes all renderers where they are used.
  82   void Notify();
  83
  84   // Notification helper to push overscroll preferences into
  85   // content.
  86   void UpdateOverscrollPrefs();
  87
  88   PrefChangeRegistrar registrar_;
  89   PrefService* prefs_;
  90
  91   DISALLOW_COPY_AND_ASSIGN(GesturePrefsObserver);
  92 };
  93
  94 // The list of prefs we want to observe.
  95 // Note that this collection of settings should correspond to the settings used
  96 // in ui/events/gestures/gesture_configuration.h
  97 const char* kPrefsToObserve[] = {
  98   prefs::kFlingAccelerationCurveCoefficient0,
  99   prefs::kFlingAccelerationCurveCoefficient1,
 100   prefs::kFlingAccelerationCurveCoefficient2,
 101   prefs::kFlingAccelerationCurveCoefficient3,
 102   prefs::kFlingMaxCancelToDownTimeInMs,
 103   prefs::kFlingMaxTapGapTimeInMs,
 104   prefs::kTabScrubActivationDelayInMS,
 105   prefs::kFlingVelocityCap,
 106   prefs::kLongPressTimeInSeconds,
 107   prefs::kMaxDistanceForTwoFingerTapInPixels,
 108   prefs::kMaxSecondsBetweenDoubleClick,
 109   prefs::kMaxSeparationForGestureTouchesInPixels,
 110   prefs::kMaxSwipeDeviationRatio,
 111   prefs::kMaxTouchDownDurationInSecondsForClick,
 112   prefs::kMaxTouchMoveInPixelsForClick,
 113   prefs::kMinDistanceForPinchScrollInPixels,
 114   prefs::kMinFlickSpeedSquared,
 115   prefs::kMinPinchUpdateDistanceInPixels,
 116   prefs::kMinRailBreakVelocity,
 117   prefs::kMinScrollDeltaSquared,
 118   prefs::kMinSwipeSpeed,
 119   prefs::kMinTouchDownDurationInSecondsForClick,
 120   prefs::kPointsBufferedForVelocity,
 121   prefs::kRailBreakProportion,
 122   prefs::kRailStartProportion,
 123   prefs::kSemiLongPressTimeInSeconds,
 124 };
 125
 126 const char* kFlingTouchpadPrefs[] = {
 127   prefs::kFlingCurveTouchpadAlpha,
 128   prefs::kFlingCurveTouchpadBeta,
 129   prefs::kFlingCurveTouchpadGamma
 130 };
 131
 132 const char* kFlingTouchscreenPrefs[] = {
 133   prefs::kFlingCurveTouchscreenAlpha,
 134   prefs::kFlingCurveTouchscreenBeta,
 135   prefs::kFlingCurveTouchscreenGamma,
 136 };
 137
 138 GesturePrefsObserver::GesturePrefsObserver(PrefService* prefs)
 139     : prefs_(prefs) {
 140   // Clear for migration.
 141   prefs->ClearPref(kMinScrollSuccessiveVelocityEvents);
 142
 143   registrar_.Init(prefs);
 144   registrar_.RemoveAll();
 145   base::Closure callback = base::Bind(&GesturePrefsObserver::Update,
 146                                       base::Unretained(this));
 147
 148   base::Closure notify_callback = base::Bind(&GesturePrefsObserver::Notify,
 149                                              base::Unretained(this));
 150
 151   for (size_t i = 0; i < arraysize(kPrefsToObserve); ++i)
 152     registrar_.Add(kPrefsToObserve[i], callback);
 153
 154   const std::vector<OverscrollPref>& overscroll_prefs = GetOverscrollPrefs();
 155   for (size_t i = 0; i < overscroll_prefs.size(); ++i)
 156     registrar_.Add(overscroll_prefs[i].pref_name, callback);
 157
 158   for (size_t i = 0; i < arraysize(kFlingTouchpadPrefs); ++i)
 159     registrar_.Add(kFlingTouchpadPrefs[i], notify_callback);
 160   for (size_t i = 0; i < arraysize(kFlingTouchscreenPrefs); ++i)
 161     registrar_.Add(kFlingTouchscreenPrefs[i], notify_callback);
 162
 163   Update();
 164 }
 165
 166 GesturePrefsObserver::~GesturePrefsObserver() {}
 167
 168 void GesturePrefsObserver::Shutdown() {
 169   registrar_.RemoveAll();
 170 }
 171
 172 void GesturePrefsObserver::Update() {
 173   GestureConfiguration::set_fling_acceleration_curve_coefficients(0,
 174       prefs_->GetDouble(prefs::kFlingAccelerationCurveCoefficient0));
 175   GestureConfiguration::set_fling_acceleration_curve_coefficients(1,
 176       prefs_->GetDouble(prefs::kFlingAccelerationCurveCoefficient1));
 177   GestureConfiguration::set_fling_acceleration_curve_coefficients(2,
 178       prefs_->GetDouble(prefs::kFlingAccelerationCurveCoefficient2));
 179   GestureConfiguration::set_fling_acceleration_curve_coefficients(3,
 180       prefs_->GetDouble(prefs::kFlingAccelerationCurveCoefficient3));
 181   GestureConfiguration::set_fling_max_cancel_to_down_time_in_ms(
 182       prefs_->GetInteger(prefs::kFlingMaxCancelToDownTimeInMs));
 183   GestureConfiguration::set_fling_max_tap_gap_time_in_ms(
 184       prefs_->GetInteger(prefs::kFlingMaxTapGapTimeInMs));
 185   GestureConfiguration::set_tab_scrub_activation_delay_in_ms(
 186       prefs_->GetInteger(prefs::kTabScrubActivationDelayInMS));
 187   GestureConfiguration::set_fling_velocity_cap(
 188       prefs_->GetDouble(prefs::kFlingVelocityCap));
 189   GestureConfiguration::set_long_press_time_in_seconds(
 190       prefs_->GetDouble(
 191           prefs::kLongPressTimeInSeconds));
 192   GestureConfiguration::set_semi_long_press_time_in_seconds(
 193       prefs_->GetDouble(
 194           prefs::kSemiLongPressTimeInSeconds));
 195   GestureConfiguration::set_max_distance_for_two_finger_tap_in_pixels(
 196       prefs_->GetDouble(
 197           prefs::kMaxDistanceForTwoFingerTapInPixels));
 198   GestureConfiguration::set_max_seconds_between_double_click(
 199       prefs_->GetDouble(
 200           prefs::kMaxSecondsBetweenDoubleClick));
 201   GestureConfiguration::set_max_separation_for_gesture_touches_in_pixels(
 202       prefs_->GetDouble(
 203           prefs::kMaxSeparationForGestureTouchesInPixels));
 204   GestureConfiguration::set_max_swipe_deviation_ratio(
 205       prefs_->GetDouble(
 206           prefs::kMaxSwipeDeviationRatio));
 207   GestureConfiguration::set_max_touch_down_duration_in_seconds_for_click(
 208       prefs_->GetDouble(
 209           prefs::kMaxTouchDownDurationInSecondsForClick));
 210   GestureConfiguration::set_max_touch_move_in_pixels_for_click(
 211       prefs_->GetDouble(
 212           prefs::kMaxTouchMoveInPixelsForClick));
 213   GestureConfiguration::set_max_distance_between_taps_for_double_tap(
 214       prefs_->GetDouble(
 215           prefs::kMaxDistanceBetweenTapsForDoubleTap));
 216   GestureConfiguration::set_min_distance_for_pinch_scroll_in_pixels(
 217       prefs_->GetDouble(
 218           prefs::kMinDistanceForPinchScrollInPixels));
 219   GestureConfiguration::set_min_flick_speed_squared(
 220       prefs_->GetDouble(
 221           prefs::kMinFlickSpeedSquared));
 222   GestureConfiguration::set_min_pinch_update_distance_in_pixels(
 223       prefs_->GetDouble(
 224           prefs::kMinPinchUpdateDistanceInPixels));
 225   GestureConfiguration::set_min_rail_break_velocity(
 226       prefs_->GetDouble(
 227           prefs::kMinRailBreakVelocity));
 228   GestureConfiguration::set_min_scroll_delta_squared(
 229       prefs_->GetDouble(
 230           prefs::kMinScrollDeltaSquared));
 231   GestureConfiguration::set_min_swipe_speed(
 232       prefs_->GetDouble(
 233           prefs::kMinSwipeSpeed));
 234   GestureConfiguration::set_min_touch_down_duration_in_seconds_for_click(
 235       prefs_->GetDouble(
 236           prefs::kMinTouchDownDurationInSecondsForClick));
 237   GestureConfiguration::set_points_buffered_for_velocity(
 238       prefs_->GetInteger(
 239           prefs::kPointsBufferedForVelocity));
 240   GestureConfiguration::set_rail_break_proportion(
 241       prefs_->GetDouble(
 242           prefs::kRailBreakProportion));
 243   GestureConfiguration::set_rail_start_proportion(
 244       prefs_->GetDouble(
 245           prefs::kRailStartProportion));
 246   GestureConfiguration::set_scroll_prediction_seconds(
 247       prefs_->GetDouble(prefs::kScrollPredictionSeconds));
 248   GestureConfiguration::set_show_press_delay_in_ms(
 249       prefs_->GetInteger(prefs::kShowPressDelayInMS));
 250
 251   UpdateOverscrollPrefs();
 252 }
 253
 254 void GesturePrefsObserver::UpdateOverscrollPrefs() {
 255   const std::vector<OverscrollPref>& overscroll_prefs = GetOverscrollPrefs();
 256   for (size_t i = 0; i < overscroll_prefs.size(); ++i) {
 257     content::SetOverscrollConfig(overscroll_prefs[i].config,
 258         static_cast<float>(prefs_->GetDouble(overscroll_prefs[i].pref_name)));
 259   }
 260 }
 261
 262 void GesturePrefsObserver::Notify() {
 263   // Must do a notify to distribute the changes to all renderers.
 264   content::NotificationService* service =
 265       content::NotificationService::current();
 266   service->Notify(chrome::NOTIFICATION_BROWSER_FLING_CURVE_PARAMETERS_CHANGED,
 267                   content::Source<GesturePrefsObserver>(this),
 268                   content::NotificationService::NoDetails());
 269 }
 270
 271 }  // namespace
 272
 273 // static
 274 GesturePrefsObserverFactoryAura*
 275 GesturePrefsObserverFactoryAura::GetInstance() {
 276   return Singleton<GesturePrefsObserverFactoryAura>::get();
 277 }
 278
 279 GesturePrefsObserverFactoryAura::GesturePrefsObserverFactoryAura()
 280     : BrowserContextKeyedServiceFactory(
 281         "GesturePrefsObserverAura",
 282         BrowserContextDependencyManager::GetInstance()) {}
 283
 284 GesturePrefsObserverFactoryAura::~GesturePrefsObserverFactoryAura() {}
 285
 286 BrowserContextKeyedService*
 287 GesturePrefsObserverFactoryAura::BuildServiceInstanceFor(
 288     content::BrowserContext* profile) const {
 289   return new GesturePrefsObserver(static_cast<Profile*>(profile)->GetPrefs());
 290 }
 291
 292 void GesturePrefsObserverFactoryAura::RegisterOverscrollPrefs(
 293     user_prefs::PrefRegistrySyncable* registry) {
 294   const std::vector<OverscrollPref>& overscroll_prefs = GetOverscrollPrefs();
 295
 296   for (size_t i = 0; i < overscroll_prefs.size(); ++i) {
 297     registry->RegisterDoublePref(
 298         overscroll_prefs[i].pref_name,
 299         content::GetOverscrollConfig(overscroll_prefs[i].config),
 300         user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 301   }
 302 }
 303
 304 void GesturePrefsObserverFactoryAura::RegisterFlingCurveParameters(
 305     user_prefs::PrefRegistrySyncable* registry) {
 306   content::RendererPreferences def_prefs;
 307
 308   for (size_t i = 0; i < arraysize(kFlingTouchpadPrefs); i++)
 309     registry->RegisterDoublePref(
 310         kFlingTouchpadPrefs[i],
 311         def_prefs.touchpad_fling_profile[i],
 312         user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 313
 314   for (size_t i = 0; i < arraysize(kFlingTouchscreenPrefs); i++)
 315     registry->RegisterDoublePref(
 316         kFlingTouchscreenPrefs[i],
 317         def_prefs.touchscreen_fling_profile[i],
 318         user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 319 }
 320
 321 void GesturePrefsObserverFactoryAura::RegisterProfilePrefs(
 322     user_prefs::PrefRegistrySyncable* registry) {
 323   registry->RegisterDoublePref(
 324       prefs::kFlingAccelerationCurveCoefficient0,
 325       GestureConfiguration::fling_acceleration_curve_coefficients(0),
 326       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 327   registry->RegisterDoublePref(
 328       prefs::kFlingAccelerationCurveCoefficient1,
 329       GestureConfiguration::fling_acceleration_curve_coefficients(1),
 330       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 331   registry->RegisterDoublePref(
 332       prefs::kFlingAccelerationCurveCoefficient2,
 333       GestureConfiguration::fling_acceleration_curve_coefficients(2),
 334       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 335   registry->RegisterDoublePref(
 336       prefs::kFlingAccelerationCurveCoefficient3,
 337       GestureConfiguration::fling_acceleration_curve_coefficients(3),
 338       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 339   registry->RegisterIntegerPref(
 340       prefs::kFlingMaxCancelToDownTimeInMs,
 341       GestureConfiguration::fling_max_cancel_to_down_time_in_ms(),
 342       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 343   registry->RegisterIntegerPref(
 344       prefs::kFlingMaxTapGapTimeInMs,
 345       GestureConfiguration::fling_max_tap_gap_time_in_ms(),
 346       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 347   registry->RegisterIntegerPref(
 348       prefs::kTabScrubActivationDelayInMS,
 349       GestureConfiguration::tab_scrub_activation_delay_in_ms(),
 350       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 351   registry->RegisterDoublePref(
 352       prefs::kFlingVelocityCap,
 353       GestureConfiguration::fling_velocity_cap(),
 354       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 355   registry->RegisterDoublePref(
 356       prefs::kLongPressTimeInSeconds,
 357       GestureConfiguration::long_press_time_in_seconds(),
 358       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 359   registry->RegisterDoublePref(
 360       prefs::kSemiLongPressTimeInSeconds,
 361       GestureConfiguration::semi_long_press_time_in_seconds(),
 362       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 363   registry->RegisterDoublePref(
 364       prefs::kMaxDistanceForTwoFingerTapInPixels,
 365       GestureConfiguration::max_distance_for_two_finger_tap_in_pixels(),
 366       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 367   registry->RegisterDoublePref(
 368       prefs::kMaxSecondsBetweenDoubleClick,
 369       GestureConfiguration::max_seconds_between_double_click(),
 370       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 371   registry->RegisterDoublePref(
 372       prefs::kMaxSeparationForGestureTouchesInPixels,
 373       GestureConfiguration::max_separation_for_gesture_touches_in_pixels(),
 374       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 375   registry->RegisterDoublePref(
 376       prefs::kMaxSwipeDeviationRatio,
 377       GestureConfiguration::max_swipe_deviation_ratio(),
 378       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 379   registry->RegisterDoublePref(
 380       prefs::kMaxTouchDownDurationInSecondsForClick,
 381       GestureConfiguration::max_touch_down_duration_in_seconds_for_click(),
 382       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 383   registry->RegisterDoublePref(
 384       prefs::kMaxTouchMoveInPixelsForClick,
 385       GestureConfiguration::max_touch_move_in_pixels_for_click(),
 386       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 387   registry->RegisterDoublePref(
 388       prefs::kMaxDistanceBetweenTapsForDoubleTap,
 389       GestureConfiguration::max_distance_between_taps_for_double_tap(),
 390       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 391   registry->RegisterDoublePref(
 392       prefs::kMinDistanceForPinchScrollInPixels,
 393       GestureConfiguration::min_distance_for_pinch_scroll_in_pixels(),
 394       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 395   registry->RegisterDoublePref(
 396       prefs::kMinFlickSpeedSquared,
 397       GestureConfiguration::min_flick_speed_squared(),
 398       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 399   registry->RegisterDoublePref(
 400       prefs::kMinPinchUpdateDistanceInPixels,
 401       GestureConfiguration::min_pinch_update_distance_in_pixels(),
 402       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 403   registry->RegisterDoublePref(
 404       prefs::kMinRailBreakVelocity,
 405       GestureConfiguration::min_rail_break_velocity(),
 406       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 407   registry->RegisterDoublePref(
 408       prefs::kMinScrollDeltaSquared,
 409       GestureConfiguration::min_scroll_delta_squared(),
 410       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 411   registry->RegisterDoublePref(
 412       prefs::kMinSwipeSpeed,
 413       GestureConfiguration::min_swipe_speed(),
 414       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 415   registry->RegisterDoublePref(
 416       prefs::kMinTouchDownDurationInSecondsForClick,
 417       GestureConfiguration::min_touch_down_duration_in_seconds_for_click(),
 418       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 419   registry->RegisterIntegerPref(
 420       prefs::kPointsBufferedForVelocity,
 421       GestureConfiguration::points_buffered_for_velocity(),
 422       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 423   registry->RegisterDoublePref(
 424       prefs::kRailBreakProportion,
 425       GestureConfiguration::rail_break_proportion(),
 426       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 427   registry->RegisterDoublePref(
 428       prefs::kRailStartProportion,
 429       GestureConfiguration::rail_start_proportion(),
 430       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 431   registry->RegisterDoublePref(
 432       prefs::kScrollPredictionSeconds,
 433       GestureConfiguration::scroll_prediction_seconds(),
 434       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 435   registry->RegisterIntegerPref(
 436       prefs::kShowPressDelayInMS,
 437       GestureConfiguration::show_press_delay_in_ms(),
 438       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 439
 440   // Register for migration.
 441   registry->RegisterIntegerPref(
 442       kMinScrollSuccessiveVelocityEvents,
 443       0,
 444       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 445
 446   RegisterOverscrollPrefs(registry);
 447   RegisterFlingCurveParameters(registry);
 448 }
 449
 450 bool
 451 GesturePrefsObserverFactoryAura::ServiceIsCreatedWithBrowserContext() const {
 452   // Create the observer as soon as the profile is created.
 453   return true;
 454 }
 455
 456 content::BrowserContext*
 457 GesturePrefsObserverFactoryAura::GetBrowserContextToUse(
 458     content::BrowserContext* context) const {
 459   // Use same gesture preferences on incognito windows.
 460   return chrome::GetBrowserContextRedirectedInIncognito(context);
 461 }
 462
 463 bool GesturePrefsObserverFactoryAura::ServiceIsNULLWhileTesting() const {
 464   // Some tests replace the PrefService of the TestingProfile after the
 465   // GesturePrefsObserver has been created, which makes Shutdown()
 466   // remove the registrar from a non-existent PrefService.
 467   return true;
 468 }