[DevTools] Support multiple sessions in Target domain

third_party/WebKit/LayoutTests/inspector-protocol/worker/worker-console.js

 (async function(testRunner) {
   let {page, session, dp} = await testRunner.startBlank('');
 
   await session.evaluate(`
     var worker = null;
     var onMessageCallbacks = {};
 
     function startWorker() {
       var callback;
       var promise = new Promise((fulfill) => callback = fulfill);
@@ skipping 21 matching lines @@
       worker.terminate();
       worker = null;
     }
   `);
 
   var workerEventHandler = {};
   dp.Target.onAttachedToTarget(onWorkerCreated);
   dp.Target.onReceivedMessageFromTarget(onWorkerMessage);
   workerEventHandler['Runtime.consoleAPICalled'] = onConsoleAPICalledFromWorker;
 
-  var workerId;
+  var workerSessionId;
 
   function onWorkerCreated(payload) {
     testRunner.log('Worker.created');
-    workerId = payload.params.targetInfo.targetId;
+    workerSessionId = payload.params.sessionId;
   }
 
   var requestId = 0;
   var dispatchTable = [];
 
   function sendCommandToWorker(method, params, callback) {
     dispatchTable[++requestId] = callback;
     var messageObject = {
       'method': method,
       'params': params,
       'id': requestId
     };
     dp.Target.sendMessageToTarget({
-      targetId: workerId,
+      sessionId: workerSessionId,
       message: JSON.stringify(messageObject)
     });
   }
 
   function onWorkerMessage(payload) {
-    if (payload.params.targetId !== workerId)
+    if (payload.params.sessionId !== workerSessionId)
       testRunner.log('targetId mismatch');
     var messageObject = JSON.parse(payload.params.message);
     var messageId = messageObject['id'];
     if (typeof messageId === 'number') {
       var handler = dispatchTable[messageId];
       dispatchTable[messageId] = null;
       if (handler && typeof handler === 'function')
         handler(messageObject);
     } else {
       var eventName = messageObject['method'];
@@ skipping 158 matching lines @@
     if (!steps.length) {
       testRunner.completeTest();
       return;
     }
     var nextStep = steps.shift();
     nextStep(runNextStep);
   }
 
   runNextStep();
 })