Add a pref for a one-time wipe of gesture prefs

chrome/browser/ui/gesture_prefs_observer_factory_aura.cc

 // Copyright (c) 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 "chrome/browser/ui/gesture_prefs_observer_factory_aura.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 133 matching lines @@
   prefs::kFlingCurveTouchscreenAlpha,
   prefs::kFlingCurveTouchscreenBeta,
   prefs::kFlingCurveTouchscreenGamma,
 };
 
 GesturePrefsObserver::GesturePrefsObserver(PrefService* prefs)
     : prefs_(prefs) {
   // Clear for migration.
   prefs->ClearPref(kTouchScreenFlingAccelerationAdjustment);
 
+  // Do a one-time wipe of all gesture preferences.
+  if (!prefs->GetBoolean(prefs::kGestureConfigIsTrustworthy)) {
+    for (size_t i = 0; i < arraysize(kPrefsToObserve); ++i)
+      prefs->ClearPref(kPrefsToObserve[i]);

[Bernhard Bauer, 2013/08/02 22:18:40]

Could you do this only if the pref has the default value?

[mohsen, 2013/08/07 05:58:04]

I thought all prefs have default values. Isn't it the case?

[Bernhard Bauer, 2013/08/07 06:01:43]

Sorry, I meant if the current user-defined value of the pref matches the default
value. That way, the user won't even see any immediate change, just if the
default changes.

[mohsen, 2013/08/07 16:28:11]

Oh, I see. This makes sense. But, the problem is that some default values might
have changed while the original bug caused the prefs to be set instead of being
cleared. So, those prefs are meant to be default but have different values than
the current default value. And, since this chrome://gesture is an internal page
and has a few users, we wanted to take this opportunity to reset all these prefs
once - e.g. for those who might have forgotten about their custom settings.

[Bernhard Bauer, 2013/08/07 16:43:52]

Hm, ok.

+
+    const std::vector<OverscrollPref>& overscroll_prefs = GetOverscrollPrefs();
+    for (size_t i = 0; i < overscroll_prefs.size(); ++i)
+      prefs->ClearPref(overscroll_prefs[i].pref_name);
+
+    for (size_t i = 0; i < arraysize(kFlingTouchpadPrefs); ++i)
+      prefs->ClearPref(kFlingTouchpadPrefs[i]);

[Bernhard Bauer, 2013/08/02 22:18:40]

Nit: newline.

[mohsen, 2013/08/07 05:58:04]

Done.

+    for (size_t i = 0; i < arraysize(kFlingTouchscreenPrefs); ++i)
+      prefs->ClearPref(kFlingTouchscreenPrefs[i]);
+
+#if defined(USE_ASH)
+    for (size_t i = 0; i < arraysize(kImmersiveModePrefs); ++i)
+      prefs->ClearPref(kImmersiveModePrefs[i]);
+#endif  // USE_ASH
+
+    prefs->SetBoolean(prefs::kGestureConfigIsTrustworthy, true);
+  }
+
   registrar_.Init(prefs);
   registrar_.RemoveAll();
   base::Closure callback = base::Bind(&GesturePrefsObserver::Update,
                                       base::Unretained(this));
 
   base::Closure notify_callback = base::Bind(&GesturePrefsObserver::Notify,
                                              base::Unretained(this));
 
   for (size_t i = 0; i < arraysize(kPrefsToObserve); ++i)
     registrar_.Add(kPrefsToObserve[i], callback);
@@ skipping 310 matching lines @@
 
   // Register for migration.
   registry->RegisterDoublePref(
       kTouchScreenFlingAccelerationAdjustment,
       0.0,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 
   RegisterOverscrollPrefs(registry);
   RegisterFlingCurveParameters(registry);
   RegisterImmersiveModePrefs(registry);
+
+  // Register pref for a one-time wipe of all gesture preferences.
+  registry->RegisterBooleanPref(
+      prefs::kGestureConfigIsTrustworthy,
+      false,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 bool
 GesturePrefsObserverFactoryAura::ServiceIsCreatedWithBrowserContext() const {
   // Create the observer as soon as the profile is created.
   return true;
 }
 
 content::BrowserContext*
 GesturePrefsObserverFactoryAura::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   // Use same gesture preferences on incognito windows.
   return chrome::GetBrowserContextRedirectedInIncognito(context);
 }
 
 bool GesturePrefsObserverFactoryAura::ServiceIsNULLWhileTesting() const {
   // Some tests replace the PrefService of the TestingProfile after the
   // GesturePrefsObserver has been created, which makes Shutdown()
   // remove the registrar from a non-existent PrefService.
   return true;
 }