update message passing from popup to background

background.js

@@ -10,17 +10,15 @@ chrome.declarativeContent.onPageChanged.removeRules(undefined, function() {
     }]);
 });
 var initial = 0;
-var a;
+var skus;
 
 chrome.extension.onMessage.addListener(function(request,sender,sendResponse){
-  chrome.storage.local.get('idArray',function(item) {
-    a = item.idArray.split(',');
-  });
-  console.log(a);
+  skus = request.idArray.split(',');
+  console.log(skus);
 });
 
 chrome.downloads.onDeterminingFilename.addListener(function(item, suggest) {
-  var new_filename = a[initial] + ".zip"; 
+  var new_filename = skus[initial] + ".zip"; 
   suggest({filename: new_filename});
   initial++;
 });

popup.js

@@ -11,7 +11,7 @@ inputButton.onclick = function(element) {
     chrome.storage.local.set({idArray : idArray}, function () {
         console.log("set storage");
     });
-    chrome.runtime.sendMessage("Message sent");
+    chrome.runtime.sendMessage({idArray: idArray});
   }); 
 }