Don't use extra variable for one-time use.

app/static/js/CorpusList.js

@@ -16,7 +16,7 @@ class CorpusList extends List {
 
 
   _update(patch) {
-    var item, operation, pathArray, valueName;
+    var item, operation, pathArray;
 
     for (operation of patch) {
       /* "/corpusId/valueName" -> ["corpusId", "valueName"] */
@@ -33,8 +33,7 @@ class CorpusList extends List {
           break;
         case "replace":
           item = this.get("id", pathArray[0])[0];
-          valueName = pathArray[1];
-          switch(valueName) {
+          switch(pathArray[1]) {
             case "description":
               item.values({"description": operation.value});
               break;

app/static/js/JobList.js

@@ -17,7 +17,7 @@ class JobList extends List {
 
   _update(patch) {
     var item, jobStatusElement, newStatusColor, operation, pathArray, status,
-        statusColor, valueName;
+        statusColor;
 
     for (operation of patch) {
       /* "/jobId/valueName" -> ["jobId", "valueName"] */
@@ -34,8 +34,7 @@ class JobList extends List {
           break;
         case "replace":
           item = this.get("id", pathArray[0])[0];
-          valueName = pathArray[1];
-          switch(valueName) {
+          switch(pathArray[1]) {
             case "description":
               item.values({"description": operation.value});
               break;