Revert "[FIX] mail: livechat escaping"

This reverts commit 1c60a631df.

The fix was done to conciliate 83956d4 and ff56304f5 but ff56304f5 was
forward-ported erroneously and introduced other issues.

opw-702410

addons/mail/static/src/js/utils.js

@@ -69,10 +69,10 @@ function linkify(text, attrs) {
     attrs = _.map(attrs, function (value, key) {
         return key + '="' + _.escape(value) + '"';
     }).join(' ');
-    return text.replace(/ /g, '\u00A0').replace(url_regexp, function (url) {
+    return text.replace(url_regexp, function (url) {
         var href = (!/^(f|ht)tps?:\/\//i.test(url)) ? "http://" + url : url;
         return '<a ' + attrs + ' href="' + href + '">' + url + '</a>';
-    }).replace(/\u00A0/g, '&nbsp;');
+    });
 }
 
 function add_link (node, transform_children) {