Justpremium Adapter: use filter instead of ...new Set (prebid#1895)

* Justpremium adapter and unit tests.

* Fix test suit.

* Performance improvements.

* Changes requested in pull request review.

* Register justpremium adapter in adaptermanager

* pass through bid from request

* fix linting errors

* Load polyfills for older browsers

* Load polyfills if older browser

* Remove package-lock.json

* Copy new Justpremium adapter from feature/1.0 branch

* prebid#1881 Requested changes applied

* prebid#1892 Use `filter` instead `...new Set` to get unique values

modules/justpremiumBidAdapter.js

@@ -17,9 +17,11 @@ export const spec = {
     const c = preparePubCond(validBidRequests)
     const dim = getWebsiteDim()
     const payload = {
-      zone: [...new Set(validBidRequests.map(b => {
+      zone: validBidRequests.map(b => {
         return parseInt(b.params.zone)
-      }))].join(','),
+      }).filter((value, index, self) => {
+        return self.indexOf(value) === index
+      }),
       hostname: getTopWindowLocation().hostname,
       protocol: getTopWindowLocation().protocol.replace(':', ''),
       sw: dim.screenWidth,