Add two new paths where webchat is available

As requested by HMRC, these two outcome pages from smart answers need
webchat assistance. The only change here is making the script load the
iframe on those two paths in addition to the self-assessment page.

app/assets/javascripts/webchat.js.erb

@@ -9,7 +9,13 @@
   var webchat = {
 
     shouldOpen: function(){
-      return (window.location.pathname === '/government/organisations/hm-revenue-customs/contact/self-assessment');
+      var webchatEnabledPaths = [
+        '/government/organisations/hm-revenue-customs/contact/self-assessment',
+        '/check-if-you-need-a-tax-return/y/employed-even-if-just-for-part-of-the-year/no/no/no-neither-of-us-claimed-child-benefit/no/no/no/none-of-these',
+        '/check-if-you-need-a-tax-return/y/retired/no/no-neither-of-us-claimed-child-benefit/no/no/no/none-of-these'
+      ];
+
+      return (webchatEnabledPaths.indexOf(window.location.pathname) >= 0);
     },
 
     validOrigin: function(origin){
@@ -42,8 +48,6 @@
 
       // IE7 can’t access webchat
       if (window.sessionStorage && window.postMessage) {
-
-        // only initialise on the self assessment help page for the time being
         if (webchat.shouldOpen()) {
 
           insertionPoint = $('.beta-wrapper').length ? $('.beta-wrapper') : $('.heading-block');