md settings: Remove level of security indicator on lock screen.

chrome/app/settings_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Settings-specific strings (included from generated_resources.grd). -->
 <grit-part>
   <!-- Main Page -->
   <if expr="chromeos">
     <message name="IDS_SETTINGS_SECONDARY_USER_BANNER" desc="Banner displayed in settings page when the user is secondary in a multi-profile session.">
       Some settings belonging to <ph name="PRIMARY_EMAIL">$1<ex>john@google.com</ex></ph> are being shared with you. These settings only affect your account when using multiple sign-in.
     </message>
   </if>
 
@@ skipping 2322 matching lines @@
     </message>
     <message name="IDS_SETTINGS_PEOPLE_CONFIGURE_PIN_MISMATCHED" desc="Message shown below the title that tells the user they have entered two different PIN values.">
       PINs do not match
     </message>
     <message name="IDS_SETTINGS_PEOPLE_CONFIGURE_PIN_CONTINUE_BUTTON" desc="A button that accepts the users initial PIN. The user will have to enter the PIN again after hitting this button to confirm that they entered it correctly.">
       Continue
     </message>
     <message name="IDS_SETTINGS_PEOPLE_ENABLE_SCREENLOCK" desc="The text on the checkbox to enable screenlocker for current user.">
       Show lock screen when waking from sleep
     </message>
-    <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_HIGH_SECURITY" desc="Text on the lock screen which indicates an unlock method is high security.">
-      High security
-    </message>
-    <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_MEDIUM_SECURITY" desc="Text on the lock screen which indicates an unlock method is medium security.">
-      Medium security
-    </message>
     <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_TITLE" desc="Text on the people page which opens up the quick unlock subpage and the title of the quick unlock subpage.">
       Screen lock
     </message>
     <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_OPTIONS" desc="Text on the lock screen which is the subheader for the screen locking options.">
       Screen lock options
     </message>
     <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_PASSWORD_ONLY" desc="Only the account password can be used to unlock the device.">
       Password only
     </message>
     <message name="IDS_SETTINGS_PEOPLE_LOCK_SCREEN_PIN_OR_PASSWORD" desc="The account password or a custom PIN can be used to unlock the device.">
@@ skipping 708 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_LABEL" desc="Label for the control that opens a user's network proxy settings.">
       Open proxy settings
     </message>
   </if>
 </grit-part>