[sessions] Properly namespace recently-componentized TabRestore code

components/sessions/core/in_memory_tab_restore_service.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 "components/sessions/core/in_memory_tab_restore_service.h"
 
 #include <vector>
 
 #include "base/compiler_specific.h"
 
-using sessions::LiveTab;
+namespace sessions {
 
 InMemoryTabRestoreService::InMemoryTabRestoreService(
-    scoped_ptr<sessions::TabRestoreServiceClient> client,
+    scoped_ptr<TabRestoreServiceClient> client,
     TabRestoreService::TimeFactory* time_factory)
     : client_(client.Pass()),
       helper_(this, NULL, client_.get(), time_factory) {}
 
 InMemoryTabRestoreService::~InMemoryTabRestoreService() {}
 
 void InMemoryTabRestoreService::AddObserver(
     TabRestoreServiceObserver* observer) {
   helper_.AddObserver(observer);
 }
@@ skipping 54 matching lines @@
   // See comment above.
   return true;
 }
 
 void InMemoryTabRestoreService::DeleteLastSession() {
   // See comment above.
 }
 
 void InMemoryTabRestoreService::Shutdown() {
 }
+
+}  // namespace