IPH - Added triggers for Download page

chrome/android/java/strings/android_chrome_strings.grd

Index: chrome/android/java/strings/android_chrome_strings.grd
diff --git a/chrome/android/java/strings/android_chrome_strings.grd b/chrome/android/java/strings/android_chrome_strings.grd
index f76d50ec04c4630a6c0fd88092daa0a2ec22cdc4..fd09618bc5bc4eb8e953d55e0a632e3543156eb6 100644
--- a/chrome/android/java/strings/android_chrome_strings.grd
+++ b/chrome/android/java/strings/android_chrome_strings.grd
@@ -2909,6 +2909,11 @@ You must have Bluetooth and Location turned on in order to use the Physical Web.
         VIDEO
       </message>
 
+      <!-- In-Product Help strings -->
+      <message name="IDS_IPH_DOWNLOAD_PAGE_FOR_OFFLINE_USAGE_TEXT" desc="The in-product-help message after a successful navigation.">
+        Download pages to use them offline
+      </message>
+
       <!-- Search Widget strings -->
       <message name="IDS_SEARCH_WIDGET_DEFAULT" desc="Default text for the search widget">
         Search