Add a do_not_sync pref to ExtensionPrefs.

chrome/browser/extensions/extension_util.h

 // Copyright 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_UTIL_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_UTIL_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 67 matching lines @@
 
 // Returns true if |extension_id| can be launched (possibly only after being
 // enabled).
 bool IsAppLaunchable(const std::string& extension_id,
                      content::BrowserContext* context);
 
 // Returns true if |extension_id| can be launched without being enabled first.
 bool IsAppLaunchableWithoutEnabling(const std::string& extension_id,
                                     content::BrowserContext* context);
 
+// Returns true if |extension| should be synced.
+bool ShouldSyncExtension(const Extension* extension,
+                         content::BrowserContext* context);
+
 // Returns true if |app| should be synced.
 bool ShouldSyncApp(const Extension* app, content::BrowserContext* context);
 
 // Returns true if |extension_id| is idle and it is safe to perform actions such
 // as updating.
 bool IsExtensionIdle(const std::string& extension_id,
                      content::BrowserContext* context);
 
 // Returns the site of the |extension_id|, given the associated |context|.
 // Suitable for use with BrowserContext::GetStoragePartitionForSite().
@@ skipping 14 matching lines @@
 
 // Returns the default extension/app icon (for extensions or apps that don't
 // have one).
 const gfx::ImageSkia& GetDefaultExtensionIcon();
 const gfx::ImageSkia& GetDefaultAppIcon();
 
 }  // namespace util
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_UTIL_H_