Migrate startup URLs pref.

chrome/browser/prefs/session_startup_pref.cc

 // Copyright (c) 2012 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/prefs/session_startup_pref.h"
 
 #include <string>
 
+#include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
+#include "base/time/time.h"
 #include "base/values.h"
 #include "base/version.h"
 #include "chrome/browser/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/net/url_fixer_upper.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_prefs/pref_registry_syncable.h"
 
 #if defined(OS_MACOSX)
 #include "chrome/browser/ui/cocoa/window_restore_utils.h"
 #endif
 
 namespace {
 
+enum StartupURLsMigrationMetrics {
+  STARTUP_URLS_MIGRATION_METRICS_PERFORMED,
+  STARTUP_URLS_MIGRATION_METRICS_NOT_PRESENT,
+  STARTUP_URLS_MIGRATION_METRICS_RESET,
+  STARTUP_URLS_MIGRATION_METRICS_MAX,
+};
+
 // Converts a SessionStartupPref::Type to an integer written to prefs.
 int TypeToPrefValue(SessionStartupPref::Type type) {
   switch (type) {
     case SessionStartupPref::LAST: return SessionStartupPref::kPrefValueLast;
     case SessionStartupPref::URLS: return SessionStartupPref::kPrefValueURLs;
     default:                       return SessionStartupPref::kPrefValueNewTab;
   }
 }
 
 void SetNewURLList(PrefService* prefs) {
@@ skipping 21 matching lines @@
 
 // static
 void SessionStartupPref::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   registry->RegisterIntegerPref(
       prefs::kRestoreOnStartup,
       TypeToPrefValue(GetDefaultStartupType()),
       user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
   registry->RegisterListPref(prefs::kURLsToRestoreOnStartup,
                              user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
+  registry->RegisterListPref(prefs::kURLsToRestoreOnStartupOld,
+                             user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterBooleanPref(
       prefs::kRestoreOnStartupMigrated,
       false,
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+  registry->RegisterInt64Pref(
+      prefs::kRestoreStartupURLsMigrationTime,
+      false,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 // static
 SessionStartupPref::Type SessionStartupPref::GetDefaultStartupType() {
 #if defined(OS_CHROMEOS)
   return SessionStartupPref::LAST;
 #else
   return SessionStartupPref::DEFAULT;
 #endif
 }
@@ skipping 50 matching lines @@
   const ListValue* url_list = prefs->GetList(prefs::kURLsToRestoreOnStartup);
   URLListToPref(url_list, &pref);
 
   return pref;
 }
 
 // static
 void SessionStartupPref::MigrateIfNecessary(PrefService* prefs) {
   DCHECK(prefs);
 
+  // Check if we need to migrate the old version of the startup URLs preference
+  // to the new name, and also send metrics about the migration.
+  StartupURLsMigrationMetrics metrics_result =
+      STARTUP_URLS_MIGRATION_METRICS_MAX;
+  const base::ListValue* old_startup_urls =
+      prefs->GetList(prefs::kURLsToRestoreOnStartupOld);
+  if (!prefs->GetUserPrefValue(prefs::kRestoreStartupURLsMigrationTime)) {
+    // Record the absence of the migration timestamp, this will get overwritten
+    // below if migration occurs now.
+    metrics_result = STARTUP_URLS_MIGRATION_METRICS_NOT_PRESENT;
+
+    // Seems like we never migrated, do it if necessary.
+    if (!prefs->GetUserPrefValue(prefs::kURLsToRestoreOnStartup)) {
+      if (old_startup_urls && !old_startup_urls->empty()) {
+        prefs->Set(prefs::kURLsToRestoreOnStartup, *old_startup_urls);
+        prefs->ClearPref(prefs::kURLsToRestoreOnStartupOld);
+      }
+      metrics_result = STARTUP_URLS_MIGRATION_METRICS_PERFORMED;
+    }
+
+    prefs->SetInt64(prefs::kRestoreStartupURLsMigrationTime,
+                    base::Time::Now().ToInternalValue());
+  } else if (old_startup_urls && !old_startup_urls->empty()) {
+    // Migration needs to be reset.
+    prefs->ClearPref(prefs::kURLsToRestoreOnStartupOld);
+    base::Time last_migration_time = base::Time::FromInternalValue(
+        prefs->GetInt64(prefs::kRestoreStartupURLsMigrationTime));
+    base::Time now = base::Time::Now();
+    prefs->SetInt64(prefs::kRestoreStartupURLsMigrationTime,
+                    now.ToInternalValue());
+    if (now < last_migration_time)
+      last_migration_time = now;
+    HISTOGRAM_CUSTOM_TIMES("Settings.StartupURLsResetTime",
+                           now - last_migration_time,
+                           base::TimeDelta::FromDays(0),
+                           base::TimeDelta::FromDays(7),
+                           50);
+    metrics_result = STARTUP_URLS_MIGRATION_METRICS_RESET;
+  }
+
+  // Record a metric migration event if something interesting happened.
+  if (metrics_result != STARTUP_URLS_MIGRATION_METRICS_MAX) {
+    UMA_HISTOGRAM_ENUMERATION(
+          "Settings.StartupURLsMigration",
+          metrics_result,
+          STARTUP_URLS_MIGRATION_METRICS_MAX);
+  }
+
   if (!prefs->GetBoolean(prefs::kRestoreOnStartupMigrated)) {
-    // Read existing values
+    // Read existing values.
     const base::Value* homepage_is_new_tab_page_value =
         prefs->GetUserPrefValue(prefs::kHomePageIsNewTabPage);
     bool homepage_is_new_tab_page = true;
     if (homepage_is_new_tab_page_value) {
       if (!homepage_is_new_tab_page_value->GetAsBoolean(
               &homepage_is_new_tab_page))
         NOTREACHED();
     }
 
     const base::Value* restore_on_startup_value =
@@ skipping 81 matching lines @@
     case kPrefValueLast:     return SessionStartupPref::LAST;
     case kPrefValueURLs:     return SessionStartupPref::URLS;
     case kPrefValueHomePage: return SessionStartupPref::HOMEPAGE;
     default:                 return SessionStartupPref::DEFAULT;
   }
 }
 
 SessionStartupPref::SessionStartupPref(Type type) : type(type) {}
 
 SessionStartupPref::~SessionStartupPref() {}