Fix situation where search nav could get stuck.

If you navigated to the ConversationActivity again via some action (like
a shared contact invite) while searching, we don't get the toolbar close
event, and therefore the search nav would stay open. Now we just reset
it on newIntent() to be safe.

src/org/thoughtcrime/securesms/conversation/ConversationActivity.java

@@ -394,6 +394,8 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
     if (fragment != null) {
       fragment.onNewIntent();
     }
+
+    searchNav.setVisibility(View.GONE);
   }
 
   @Override