MD History: Add icon in top right of page when showing synced results

components/history_strings.grdp

Index: components/history_strings.grdp
diff --git a/components/history_strings.grdp b/components/history_strings.grdp
index f73f49e78489812e11b90a33a23fb6202f408e93..628572cd4987cdb95d4595c5f9f7b78462af3d64 100644
--- a/components/history_strings.grdp
+++ b/components/history_strings.grdp
@@ -53,7 +53,10 @@ Psst! Incognito mode <ph name="SHORTCUT_KEY">$1<ex>(Ctrl+Shift+N)</ex></ph> may
     Found <ph name="NUMBER_OF_RESULTS">$1</ph> <ph name="SEARCH_RESULTS"><ex>search results</ex>$2</ph> for '<ph name="SEARCH_STRING">$3</ph>'.
   </message>
   <message name="IDS_HISTORY_HAS_SYNCED_RESULTS" desc="The notification at the top of the history page indicating that it is showing visits synced from other devices.">
-    Showing history from your signed-in devices. <ph name="BEGIN_LINK">&lt;a href="https://support.google.com/chrome/?p=sync_history&amp;hl=[GRITLANGCODE]"&gt;</ph>Learn more<ph name="END_LINK">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>.
+    Showing history from your signed-in devices. <ph name="BEGIN_LINK">&lt;a href="https://support.google.com/chrome/?p=sync_history&amp;hl=[GRITLANGCODE]"&gt;</ph>Learn more<ph name="END_LINK">&lt;/a&gt;<ex>&lt;/a&gt;</ex></ph>
+  </message>
+  <message name="IDS_HISTORY_HAS_SYNCED_RESULTS_DESCRIPTION" desc="Description for the notification at the top of the history page indicating that it is showing visits synced from other devices. This is spoken by the screen reader when the notification button is focused.">
+    Showing history from your signed-in devices.
   </message>
   <message name="IDS_HISTORY_OTHER_FORMS_OF_HISTORY" desc="The notification at the top of the history page indicating that deleting Chrome browsing history will not delete other forms of history stored at Google My Activity.">
     Your Google Account may have other forms of browsing history at <ph name="BEGIN_LINK">&lt;a target="_blank" href="$1"&gt;</ph>history.google.com<ph name="END_LINK">&lt;/a&gt;</ph>.