refactor: Improve var name. b/131773884 (#1262)

* refactor: Improve var name. b/131773884

* Update index.js

Author: grant

functions/node8/index.js

@@ -98,13 +98,12 @@ exports.helloBackground = (data, context) => {
  * This function is exported by index.js, and executed when
  * the trigger topic receives a message.
  *
- * @param {object} data The event payload.
+ * @param {object} pubSubEvent The event payload.
  * @param {object} context The event metadata.
  */
-exports.helloPubSub = (data, context) => {
-  const pubSubMessage = data;
-  const name = pubSubMessage.data
-    ? Buffer.from(pubSubMessage.data, 'base64').toString()
+exports.helloPubSub = (pubSubEvent, context) => {
+  const name = pubSubEvent.data
+    ? Buffer.from(pubSubEvent.data, 'base64').toString()
     : 'World';
 
   console.log(`Hello, ${name}!`);