[inspector] Refactor protocol-test.js

test/inspector/debugger/set-script-source.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-InspectorTest.addScript(
+let {session, contextGroup, Protocol} = InspectorTest.start('Tests Debugger.setScriptSource');
+
+contextGroup.addScript(
 `function TestExpression(a, b) {
     return a + b;
 }`);
 
 // A general-purpose engine for sending a sequence of protocol commands.
 // The clients provide requests and response handlers, while the engine catches
 // errors and makes sure that once there's nothing to do completeTest() is called.
 // @param step is an object with command, params and callback fields
 function runRequestSeries(step) {
   processStep(step);
@@ skipping 127 matching lines @@
 
   function errorCallbackSetScriptSource2(result) {
     var exceptionDetails = result.exceptionDetails;
     logCheck("Has error reported", !!exceptionDetails);
     logCheck("Reported error is a compile error", !!exceptionDetails);
     if (exceptionDetails)
       logEqualsCheck(exceptionDetails.lineNumber, 1);
     return next;
   }
 }