Add checkbox to allow auto signing in with a saved password.

chrome/app/settings_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Settings-specific strings (included from generated_resources.grd). -->
 <grit-part>
   <!-- About Page -->
   <if expr="chromeos">
     <message name="IDS_SETTINGS_ABOUT_PAGE_DETAILED_BUILD_INFO" desc="Label describing the section that shows detailed information about the current Chrome build.">
       Detailed build information
     </message>
     <message name="IDS_SETTINGS_ABOUT_PAGE_ARC_VERSION" desc="Label for ARC version">
       ARC Version
@@ skipping 299 matching lines @@
   </message>
   <message name="IDS_SETTINGS_CREDIT_CARD_EXPIRATION_MONTH" desc="Accessibility label on the month drop down to let users know the field corresponds to the expiration month">
     Expiration month
   </message>
   <message name="IDS_SETTINGS_CREDIT_CARD_EXPIRATION_YEAR" desc="Accessibility label on the year drop down to let users know the field corresponds to the expiration year">
     Expiration year
   </message>
   <message name="IDS_SETTINGS_PASSWORDS" desc="Name for the password section and toggle">
     Manage passwords
   </message>
+  <message name="IDS_SETTINGS_PASSWORDS_AUTOSIGNIN_CHECKBOX_LABEL" desc="Label for a checkbox that allows users to sign in automatically to websites when their credentials are already saved.">
+    Auto Sign-in
+  </message>
+  <message name="IDS_SETTINGS_PASSWORDS_AUTOSIGNIN_CHECKBOX_DESC" desc="Text that describes the 'Auto Sign-in' functionality to users.">
+    Automatically sign in to websites using stored credentials. When the feature is disabled, you will be asked for confirmation every time before signing in to a website.
+  </message>
   <message name="IDS_SETTINGS_PASSWORDS_DETAIL" desc="Description of what toggling the 'Manage passwords' setting does. Immediately underneath IDS_SETTINGS_PASSWORDS">
     Offer to save your web passwords
   </message>
   <message name="IDS_SETTINGS_PASSWORDS_SAVED_HEADING" desc="The title for a list of username/site/password items. These items are already saved by the browser and can be deleted/edited.">
     Saved Passwords
   </message>
   <message name="IDS_SETTINGS_PASSWORDS_EXCEPTIONS_HEADING" desc="The title for a list of sites where passwords will not be saved. These items are already saved by the browser and can only be deleted.">
     Never Saved
   </message>
   <message name="IDS_SETTINGS_PASSWORDS_DELETE_EXCEPTION" desc="The alt text for a button that deletes a site for which passwords would not be saved.">
@@ skipping 1561 matching lines @@
       System
     </message>
     <message name="IDS_SETTINGS_SYSTEM_HARDWARE_ACCELERATION_LABEL" desc="Label for the checkbox that forces Chrome to render via hardware acceleration (GPU) when available.">
       Use hardware acceleration when available
     </message>
     <message name="IDS_SETTINGS_SYSTEM_PROXY_SETTINGS_BUTTON" desc="Text for the button that changes a user's network proxy settings.">
       Change proxy settings
     </message>
   </if>
 </grit-part>