Correct the flag: is_extension_upgrade, which denote whether the extension is being upgrading.

chrome/browser/extensions/extension_service.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 747 matching lines @@
   void FinishInstallation(const extensions::Extension* extension);
 
   // Updates the |extension|'s active permission set to include only permissions
   // currently requested by the extension and all the permissions required by
   // the extension.
   void UpdateActivePermissions(const extensions::Extension* extension);
 
   // Disables the extension if the privilege level has increased
   // (e.g., due to an upgrade).
   void CheckPermissionsIncrease(const extensions::Extension* extension,
-                                bool is_upgrade);
+                                bool is_extension_installed);
 
   // Helper that updates the active extension list used for crash reporting.
   void UpdateActiveExtensionsInCrashReporter();
 
   // Helper to inspect an ExtensionHost after it has been loaded.
   void InspectExtensionHost(extensions::ExtensionHost* host);
 
   // Helper to determine whether we should initially enable an installed
   // (or upgraded) extension.
   bool ShouldEnableOnInstall(const extensions::Extension* extension);
@@ skipping 178 matching lines @@
   syncer::SyncableService::StartSyncFlare flare_;
 
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsWithUnlimtedStorage);
   FRIEND_TEST_ALL_PREFIXES(ExtensionServiceTest,
                            InstallAppsAndCheckStorageProtection);
   DISALLOW_COPY_AND_ASSIGN(ExtensionService);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_SERVICE_H_