Make possible restarting extensions from the chrome://extensions/ page....

chrome/browser/extensions/extensions_service.cc

 // Copyright (c) 2009 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/extensions/extensions_service.h"
 
 #include "app/l10n_util.h"
 #include "base/command_line.h"
 #include "base/crypto/signature_verifier.h"
 #include "base/file_util.h"
@@ skipping 336 matching lines @@
         << "installed";
     FireInstallCallback(extension_path, NULL);
     return;
   }
 
   backend_loop_->PostTask(FROM_HERE, NewRunnableMethod(backend_.get(),
       &ExtensionsServiceBackend::UpdateExtension, id, extension_path,
       alert_on_error, scoped_refptr<ExtensionsService>(this)));
 }
 
+void ExtensionsService::ReloadExtension(const std::string& extension_id) {
+  Extension* extension = GetExtensionById(extension_id);
+  FilePath extension_path = extension->path();
+
+  UnloadExtension(extension_id);
+  LoadExtension(extension_path);
+}
+
 void ExtensionsService::UninstallExtension(const std::string& extension_id,
                                            bool external_uninstall) {
   Extension* extension = GetExtensionById(extension_id);
 
   // Callers should not send us nonexistant extensions.
   DCHECK(extension);
 
   extension_prefs_->OnExtensionUninstalled(extension, external_uninstall);
 
   // Tell the backend to start deleting installed extensions on the file thread.
@@ skipping 1135 matching lines @@
   Extension::InstallType install_type =
       CompareToInstalledVersion(id, version->GetString(), &current_version);
 
   if (install_type == Extension::DOWNGRADE)
     return false;
 
   return (install_type == Extension::UPGRADE ||
           install_type == Extension::NEW_INSTALL ||
           NeedsReinstall(id, current_version));
 }