Make ide opening flow partly aware of multiple domains

node_modules/c9/urls.js

@@ -34,6 +34,8 @@ plugin.getBaseUrl = function(req, sourceBaseUrlPattern, targetBaseUrlPattern) {
         || req.host
         || req.url && req.url.replace(/^https?:\/\/([^/]*).*/, "$1")
         || req;
+    assert(!sourceHost.match(/\$DOMAIN/), "Please provide a valid request object");
+
     var sourceHostMatcher = sourceBaseUrlPattern
         .replace(/^https?:\/\//, "")
         .replace(/\/.*/, "")