Show special string in SignInPreference summary when signin is disabled

chrome/android/java/strings/android_chrome_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!-- android_chrome_strings.grd contains strings for Chrome for Android.
 
 FAQ:
   - How do I add, change, or remove a string?
       Just update this file.
   - Translations will happen automatically??
       Yes, indeed. Just add your string before the branch point and
       make the description good.
@@ skipping 252 matching lines @@
         Sites
       </message>
 
       <!-- Sign-in preference -->
       <message name="IDS_SIGN_IN_TO_CHROME" desc="Title for the button to sign in to Chrome using one's Google account. [CHAR-LIMIT=27]">
         Sign in to Chrome
       </message>
       <message name="IDS_SIGN_IN_TO_CHROME_SUMMARY" desc="Summary for the button to sign in to Chrome, explaining benefits of signing in.">
         Sign in to get your bookmarks, history, passwords, and other settings on all your devices
       </message>
+      <message name="IDS_SIGN_IN_TO_CHROME_DISABLED_SUMMARY" desc="Summary for disabled button to sign in to Chrome when signin is disabled by the device administrator.">

[gone, 2017/05/03 20:41:52]

I think you need to ask Shimi about the description string, too.

+          Disabled by the administrator of this device
+      </message>
       <message name="IDS_SIGN_IN_GOOGLE_ACTIVITY_CONTROLS" desc="Title of Google activity controls preference in signed in accounts settings screen">
         Google Activity Controls
       </message>
       <message name="IDS_SIGN_IN_GOOGLE_ACTIVITY_CONTROLS_MESSAGE" desc="Message of Google activity controls preference in signed in accounts settings screen">
         Control how Google uses your browsing history to personalize Search, ads, and other Google services.
       </message>
       <message name="IDS_SIGN_IN_GOOGLE_ACTIVITY_CONTROLS_MESSAGE_CHILD_ACCOUNT" desc="Message of Google activity controls preference in signed in accounts settings screen for child accounts">
         Control how Google uses your browsing history to personalize Search and other Google services.
       </message>
       <message name="IDS_SIGN_IN_SYNC_ERROR_WIDGET" desc="Accessibility description of the sync error widget in settings screen">
@@ skipping 2694 matching lines @@
         Remove and recreate this shortcut
       </message>
 
       <!-- Chrome Home -->
       <message name="IDS_BOTTOM_SHEET_HELP_BUBBLE_MESSAGE" desc="Text displayed in a help bubble above the bottom navigation sheet prompting users to pull the sheet up to see their bookmarks and other content.">
         Pull up to see bookmarks and more
       </message>
     </messages>
   </release>
 </grit>