Remove some obsolete prefs.

Review-Url: https://codereview.chromium.org/2320723002
Cr-Commit-Position: refs/heads/master@{#417235}

components/content_settings/core/browser/content_settings_default_provider.cc

@@ -9,7 +9,6 @@
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
-#include "base/command_line.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
 #include "components/content_settings/core/browser/content_settings_rule.h"
@@ -29,15 +28,6 @@ namespace content_settings {
 
 namespace {
 
-// Obsolete prefs to be removed from the pref file.
-// TODO(msramek): Remove this cleanup code after two releases (i.e. in M50).
-const char kObsoleteMetroSwitchToDesktopSetting[] =
-    "profile.default_content_setting_values.metro_switch_to_desktop";
-
-// TODO(msramek): Remove this cleanup code after two releases (i.e. in M51).
-const char kObsoleteMediaStreamSetting[] =
-    "profile.default_content_setting_values.media_stream";
-
 ContentSetting GetDefaultValue(const WebsiteSettingsInfo* info) {
   const base::Value* initial_default = info->initial_default_value();
   if (!initial_default)
@@ -91,17 +81,6 @@ void DefaultProvider::RegisterProfilePrefs(
                                   GetDefaultValue(info),
                                   info->GetPrefRegistrationFlags());
   }
-
-  // Obsolete prefs -------------------------------------------------------
-
-  // The removed content settings type METRO_SWITCH_TO_DESKTOP.
-  registry->RegisterIntegerPref(
-      kObsoleteMetroSwitchToDesktopSetting,
-      0,
-      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
-
-  // The removed content settings type MEDIASTREAM.
-  registry->RegisterIntegerPref(kObsoleteMediaStreamSetting, 0);
 }
 
 DefaultProvider::DefaultProvider(PrefService* prefs, bool incognito)
@@ -110,9 +89,6 @@ DefaultProvider::DefaultProvider(PrefService* prefs, bool incognito)
       updating_preferences_(false) {
   DCHECK(prefs_);
 
-  // Remove the obsolete preferences from the pref file.
-  DiscardObsoletePreferences();
-
   // Read global defaults.
   ReadDefaultSettings();
 
@@ -367,9 +343,4 @@ std::unique_ptr<base::Value> DefaultProvider::ReadFromPref(
   return ContentSettingToValue(IntToContentSetting(int_value));
 }
 
-void DefaultProvider::DiscardObsoletePreferences() {
-  prefs_->ClearPref(kObsoleteMetroSwitchToDesktopSetting);
-  prefs_->ClearPref(kObsoleteMediaStreamSetting);
-}
-
 }  // namespace content_settings

components/content_settings/core/browser/content_settings_default_provider.h

@@ -72,16 +72,13 @@ class DefaultProvider : public ObservableProvider {
   // Called on prefs change.
   void OnPreferenceChanged(const std::string& pref_name);
 
-  // Clean up the obsolete preferences from the user's profile.
-  void DiscardObsoletePreferences();
-
   // Copies of the pref data, so that we can read it on the IO thread.
   std::map<ContentSettingsType, std::unique_ptr<base::Value>> default_settings_;
 
   PrefService* prefs_;
 
   // Whether this settings map is for an Incognito session.
-  bool is_incognito_;
+  const bool is_incognito_;
 
   // Used around accesses to the |default_settings_| object to guarantee
   // thread safety.

components/content_settings/core/browser/content_settings_pref_provider.cc

@@ -15,7 +15,6 @@
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
-#include "base/strings/string_split.h"
 #include "base/time/clock.h"
 #include "base/time/default_clock.h"
 #include "components/content_settings/core/browser/content_settings_pref.h"
@@ -32,18 +31,6 @@
 #include "components/prefs/pref_service.h"
 #include "components/prefs/scoped_user_pref_update.h"
 
-namespace {
-
-// Obsolete prefs.
-// TODO(msramek): Remove the cleanup code after two releases (i.e. in M50).
-const char kObsoleteMetroSwitchToDesktopExceptions[] =
-    "profile.content_settings.exceptions.metro_switch_to_desktop";
-
-const char kObsoleteMediaStreamExceptions[] =
-    "profile.content_settings.exceptions.media_stream";
-
-}  // namespace
-
 namespace content_settings {
 
 // ////////////////////////////////////////////////////////////////////////////
@@ -63,14 +50,6 @@ void PrefProvider::RegisterProfilePrefs(
     registry->RegisterDictionaryPref(info->pref_name(),
                                      info->GetPrefRegistrationFlags());
   }
-
-  // Obsolete prefs ----------------------------------------------------------
-
-  registry->RegisterDictionaryPref(
-      kObsoleteMetroSwitchToDesktopExceptions,
-      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
-
-  registry->RegisterDictionaryPref(kObsoleteMediaStreamExceptions);
 }
 
 PrefProvider::PrefProvider(PrefService* prefs, bool incognito)
@@ -109,8 +88,6 @@ PrefProvider::PrefProvider(PrefService* prefs, bool incognito)
     UMA_HISTOGRAM_COUNTS("ContentSettings.NumberOfExceptions",
                          num_exceptions);
   }
-
-  DiscardObsoletePreferences();
 }
 
 PrefProvider::~PrefProvider() {
@@ -210,9 +187,4 @@ void PrefProvider::Notify(
                   resource_identifier);
 }
 
-void PrefProvider::DiscardObsoletePreferences() {
-  prefs_->ClearPref(kObsoleteMetroSwitchToDesktopExceptions);
-  prefs_->ClearPref(kObsoleteMediaStreamExceptions);
-}
-
 }  // namespace content_settings

components/content_settings/core/browser/content_settings_pref_provider.h

@@ -80,16 +80,13 @@ class PrefProvider : public ObservableProvider {
               ContentSettingsType content_type,
               const std::string& resource_identifier);
 
-  // Clean up the obsolete preferences from the user's profile.
-  void DiscardObsoletePreferences();
-
   // Weak; owned by the Profile and reset in ShutdownOnUIThread.
   PrefService* prefs_;
 
   // Can be set for testing.
   std::unique_ptr<base::Clock> clock_;
 
-  bool is_incognito_;
+  const bool is_incognito_;
 
   PrefChangeRegistrar pref_change_registrar_;