Make some code gender neutral.

chrome/browser/ui/user_manager.h

Index: chrome/browser/ui/user_manager.h
diff --git a/chrome/browser/ui/user_manager.h b/chrome/browser/ui/user_manager.h
index e7290dfe6c288c2fa431e0f10de55b7edfdb41a9..1173d049bb0db70ce6c5997a8876aff3f5487749 100644
--- a/chrome/browser/ui/user_manager.h
+++ b/chrome/browser/ui/user_manager.h
@@ -73,8 +73,8 @@ class UserManager {
   // Hides the reauth dialog if it is showing.
   static void HideReauthDialog();
 
-  // Shows a dialog where the user login his or her profile by the first time
-  // via user manager.
+  // Shows a dialog where the user logs into their profile for the first time
+  // via the user manager.
   static void ShowSigninDialog(content::BrowserContext* browser_context,
                                const base::FilePath& profile_path);