MD Settings: Eliminate use of ES6 for Chrome OS

ui/webui/resources/cr_elements/network/cr_network_list_item.js

Index: ui/webui/resources/cr_elements/network/cr_network_list_item.js
diff --git a/ui/webui/resources/cr_elements/network/cr_network_list_item.js b/ui/webui/resources/cr_elements/network/cr_network_list_item.js
index 8d3841daa869ec6bf4ba3ff664d2aa7101a8b8a4..a6946ca5a8078deb7bf1829871675081b6682df2 100644
--- a/ui/webui/resources/cr_elements/network/cr_network_list_item.js
+++ b/ui/webui/resources/cr_elements/network/cr_network_list_item.js
@@ -84,13 +84,13 @@ Polymer({
    */
   getItemName_: function() {
     if (this.item.hasOwnProperty('customItemName')) {
-      let item = /** @type {!CrNetworkList.CustomItemState} */ (this.item);
-      let name = item.customItemName || '';
+      var item = /** @type {!CrNetworkList.CustomItemState} */ (this.item);
+      var name = item.customItemName || '';
       if (CrOncStrings.hasOwnProperty(item.customItemName))
         name = CrOncStrings[item.customItemName];
       return name;
     }
-    let network = /** @type {!CrOnc.NetworkStateProperties} */ (this.item);
+    var network = /** @type {!CrOnc.NetworkStateProperties} */ (this.item);
     if (this.isListItem)
       return CrOnc.getNetworkName(network);
     return CrOncStrings['OncType' + network.Type];