[protector] Bump Preferences backup version to 3 to mitigate the startup prefs migration.

Since r134147 (https://chromiumcodereview.appspot.com/10213009), startup prefs migration is more complex and may trigger the protector for users on M19.


BUG=122936
TEST=ProtectedPrefsWatcherTest.*


Review URL: http://codereview.chromium.org/10170046

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@134698 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/protector/protected_prefs_watcher.cc

@@ -63,7 +63,7 @@ void StringAppendStringDictionary(const base::DictionaryValue* dict,
 }  // namespace
 
 // static
-const int ProtectedPrefsWatcher::kCurrentVersionNumber = 2;
+const int ProtectedPrefsWatcher::kCurrentVersionNumber = 3;
 
 ProtectedPrefsWatcher::ProtectedPrefsWatcher(Profile* profile)
     : is_backup_valid_(true),
@@ -208,8 +208,18 @@ void ProtectedPrefsWatcher::MigrateOldBackupIfNeeded() {
 
   switch (current_version) {
     case 1:
+      // Add pinned tabs.
       prefs->Set(kBackupPinnedTabs, *prefs->GetList(prefs::kPinnedTabs));
       // FALL THROUGH
+
+    case 2:
+      // SessionStartupPref migration.
+      DCHECK(prefs->GetBoolean(prefs::kRestoreOnStartupMigrated));
+      prefs->SetInteger(kBackupRestoreOnStartup,
+                        prefs->GetInteger(prefs::kRestoreOnStartup));
+      prefs->Set(kBackupURLsToRestoreOnStartup,
+                 *prefs->GetList(prefs::kURLsToRestoreOnStartup));
+      // FALL THROUGH
   }
 
   prefs->SetInteger(kBackupVersion, kCurrentVersionNumber);

chrome/browser/protector/protected_prefs_watcher_unittest.cc

@@ -189,4 +189,34 @@ TEST_F(ProtectedPrefsWatcherTest, MigrationToVersion2) {
             prefs_->GetInteger("backup._version"));
 }
 
+// Verify that SessionStartupPref migration doesn't trigger Protector
+// (version 3 migration).
+TEST_F(ProtectedPrefsWatcherTest, MigrationToVersion3) {
+  EXPECT_TRUE(prefs_watcher_->is_backup_valid());
+
+  // Bring startup prefs to an old (pre-migration) version.
+  prefs_->SetBoolean(prefs::kHomePageIsNewTabPage, false);
+  prefs_->SetString(prefs::kHomePage, "http://example.com/");
+  prefs_->ClearPref(prefs::kRestoreOnStartupMigrated);
+
+  // Reset version to 2 and overwrite the signature.
+  prefs_->SetInteger("backup._version", 2);
+  ForceUpdateSignature();
+  EXPECT_TRUE(IsSignatureValid());
+
+  // Take down the old instance and create a new ProtectedPrefsWatcher from
+  // current prefs.
+  ProtectorServiceFactory::GetForProfile(&profile_)->
+      StopWatchingPrefsForTesting();
+  scoped_ptr<ProtectedPrefsWatcher> prefs_watcher2(
+      new ProtectedPrefsWatcher(&profile_));
+  EXPECT_TRUE(prefs_watcher2->is_backup_valid());
+
+  // Startup settings shouldn't be reported as changed.
+  EXPECT_FALSE(prefs_watcher2->DidPrefChange(prefs::kRestoreOnStartup));
+  EXPECT_FALSE(prefs_watcher2->DidPrefChange(prefs::kURLsToRestoreOnStartup));
+  EXPECT_EQ(ProtectedPrefsWatcher::kCurrentVersionNumber,
+            prefs_->GetInteger("backup._version"));
+}
+
 }  // namespace protector

chrome/browser/protector/protector_service.cc

@@ -119,6 +119,10 @@ ProtectedPrefsWatcher* ProtectorService::GetPrefsWatcher() {
   return prefs_watcher_.get();
 }
 
+void ProtectorService::StopWatchingPrefsForTesting() {
+  prefs_watcher_.reset();
+}
+
 ProtectorService::Item* ProtectorService::FindItemToMergeWith(
     const BaseSettingChange* change) {
   if (!change->CanBeMerged())

chrome/browser/protector/protector_service.h

@@ -62,6 +62,10 @@ class ProtectorService : public ProfileKeyedService,
   // backup.
   ProtectedPrefsWatcher* GetPrefsWatcher();
 
+  // Stops observing pref changes and updating the backup. Should be used in
+  // tests only.
+  void StopWatchingPrefsForTesting();
+
   // Returns the most recent change instance or NULL if there are no changes.
   BaseSettingChange* GetLastChange();