Improve grammar in some comments.

ash/common/system/user/tray_user_unittest.cc

 // 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.
 
 #include <vector>
 
 #include "ash/common/shell_delegate.h"
 #include "ash/common/system/tray/system_tray.h"
 #include "ash/common/system/tray/tray_constants.h"
 #include "ash/common/system/user/tray_user.h"
@@ skipping 187 matching lines @@
     // Set the number of logged in users.
     delegate()->set_logged_in_users(j);
 
     // Verify that nothing is shown.
     EXPECT_FALSE(tray()->IsAnyBubbleVisible());
     for (int i = 0; i < max_users; i++)
       EXPECT_FALSE(tray_user(i)->GetStateForTest());
     EXPECT_FALSE(tray_user_separator()->separator_shown());
     // After clicking on the tray the menu should get shown and for each logged
     // in user we should get a visible item. In addition, the separator should
-    // show up when we reach more then one user.
+    // show up when we reach more than one user.
     ShowTrayMenu(&generator);
 
     EXPECT_TRUE(tray()->HasSystemBubble());
     EXPECT_TRUE(tray()->IsAnyBubbleVisible());
     for (int i = 0; i < max_users; i++) {
       EXPECT_EQ(i < j ? TrayUser::SHOWN : TrayUser::HIDDEN,
                 tray_user(i)->GetStateForTest());
     }
 
     // Check the visibility of the separator.
@@ skipping 40 matching lines @@
   // Since the name is capitalized, the email should be different then the
   // user_id.
   EXPECT_NE(active_user->GetAccountId().GetUserEmail(),
             second_user->GetEmail());
   tray()->CloseSystemBubble();
 }
 
 #endif
 
 }  // namespace ash