Add new NTP layout with snippet cards and hide it behind a flag

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 1803 matching lines @@
       <message name="IDS_RECENTLY_CLOSED" desc="Header for the list of recently closed tabs">
         Recently closed
       </message>
       <message name="IDS_SHOW_FULL_HISTORY" desc="Link text to go to the history page from the recent tabs page.">
         Show full history
       </message>
       <message name="IDS_REMOVE_ALL" desc="Context menu option to clear the list of recently closed tabs">
         Remove all
       </message>
       <message name="IDS_SNIPPETS_HEADER" desc="Header for a group of content snippets">
-        For readers of <ph name="PUBLISHER">%1$s<ex>The New York Times</ex></ph>
-      </message>
-      <message name="IDS_SNIPPETS_NTP_READ_MORE_LINK_TEXT" desc="Link to an article this snippet is describing">
-        Read more
+        Articles for you
       </message>
 
       <!-- Toolbar button strings -->
       <message name="IDS_OPEN_TABS" desc="Text for button to enter the tab switcher and show tabs that are open on this device">
         Open tabs
       </message>
       <message name="IDS_BUTTON_NEW_TAB" desc="Button name for opening a new tab.">
         New tab
       </message>
 
@@ skipping 563 matching lines @@
       </message>
       <message name="IDS_USB_CHOOSER_DIALOG_CONNECT_BUTTON_TEXT" desc="The text that is shown on the connect button in the USB chooser dialog.">
         Connect
       </message>
       <message name="IDS_USB_CHOOSER_DIALOG_FOOTNOTE_TEXT" desc="This text is shown at the bottom of the USB chooser dialog with a link to part of its text.">
         Not seeing your device? <ph name="BEGIN_LINK">&lt;link&gt;</ph>Get help<ph name="END_LINK">&lt;/link&gt;</ph>
       </message>
     </messages>
   </release>
 </grit>