[ServiceWorker] Update formatting for tests.

LayoutTests/http/tests/serviceworker/resources/request-end-to-end-worker.js

 var port = undefined;
 
 onmessage = function(e) {
-    var message = e.data;
-    if (typeof message === 'object' && 'port' in message) {
-        port = message.port;
-    }
+  var message = e.data;
+  if (typeof message === 'object' && 'port' in message) {
+    port = message.port;
+  }
 };
 
 onfetch = function(e) {
-    var headers = {};
-    for (var header of e.request.headers) {
-      var key = header[0], value = header[1];
-      headers[key] = value;
-    }
-    port.postMessage({
-        url: e.request.url,
-        method: e.request.method,
-        headers: headers,
-        headerSize: e.request.headers.size
+  var headers = {};
+  for (var header of e.request.headers) {
+    var key = header[0], value = header[1];
+    headers[key] = value;
+  }
+  port.postMessage({
+      url: e.request.url,
+      method: e.request.method,
+      headers: headers,
+      headerSize: e.request.headers.size
     });
-}
+};