Added strings of i18n and made the pin-keyboard work for rtl lang.

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_CHECK_FOR_UPDATES" desc="The button label to check for updates and apply (download and install) if found">
       Check for updates
     </message>
     <message name="IDS_SETTINGS_ABOUT_PAGE_CURRENT_CHANNEL_STABLE" desc="The stable label in the message about current channel.">
       stable
@@ skipping 1156 matching lines @@
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_CHOOSE_UNLOCK_METHOD" desc="Text below the page title that tells the user to select a method to unlock the device. This is *only* for unlocking a device; it cannot be used to sign into a device.">
       Choose the method you would like to use to log back in to your account:
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_UNLOCK_METHOD_PASSWORD" desc="Only the account password can be used to unlock the device.">
       Only password
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_UNLOCK_METHOD_PIN_AND_PASSWORD" desc="The account password or a custom PIN can be used to unlock the device.">
       PIN or password
     </message>
+    <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_ENTER_PIN_OR_PASSWORD_PLACEHOLDER" desc="Placeholder for input box before PIN is entered.">
+      Enter PIN
+    </message>
+    <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_PIN_KEYBOARD_CLEAR" desc="The text of the button on the pin keyboard used to delete last character of entered PIN.">
+      Clear
+    </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_UNLOCK_METHOD_NONE" desc="After the device resumes, there will not be a lock screen and no password of any type will be required.">
       None
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_CONFIGURE_PIN_BUTTON" desc="Button that is only shown when the user has selected PIN as their unlock method. This button opens up the configuration flow where the user selects the PIN they would like to use.">
       Configure PIN
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_CONFIGURE_PIN_CHOOSE_PIN_TITLE" desc="Message shown below the title that tells the user to enter the initial PIN.">
       Choose your PIN:
     </message>
     <message name="IDS_SETTINGS_PEOPLE_QUICK_UNLOCK_CONFIGURE_PIN_CHOOSE_PIN_WEAK_PIN_WARNING" desc="Message shown below the title that warns the user they have entered a PIN that is easy to guess.">
@@ skipping 428 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>