[inspector] Refactor protocol-test.js

test/inspector/debugger/stepping-with-natives-and-frameworks.js

 // Copyright 2017 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.log('Stepping with natives and frameworks.');
+let {session, contextGroup, Protocol} = InspectorTest.start('Stepping with natives and frameworks.');
 
-InspectorTest.addScript(`
+contextGroup.addScript(`
 function callAll() {
   for (var f of arguments)
     f();
 }
 //# sourceURL=framework.js`);
 
-InspectorTest.setupScriptMap();
+session.setupScriptMap();
 InspectorTest.logProtocolCommandCalls('Debugger.pause');
 InspectorTest.logProtocolCommandCalls('Debugger.stepInto');
 InspectorTest.logProtocolCommandCalls('Debugger.stepOver');
 InspectorTest.logProtocolCommandCalls('Debugger.stepOut');
 InspectorTest.logProtocolCommandCalls('Debugger.resume');
 
 Protocol.Debugger.enable();
 Protocol.Debugger.setBlackboxPatterns({patterns: ['framework\.js']});
 InspectorTest.runAsyncTestSuite([
   async function testNativeCodeStepOut() {
@@ skipping 264 matching lines @@
     await logPauseLocation(await Protocol.Debugger.oncePaused());
     Protocol.Debugger.stepOut();
     await logPauseLocation(await Protocol.Debugger.oncePaused());
     Protocol.Debugger.stepOut();
     await logPauseLocation(await Protocol.Debugger.oncePaused());
     await Protocol.Debugger.resume();
   }
 ]);
 
 function logPauseLocation(message) {
-  return InspectorTest.logSourceLocation(message.params.callFrames[0].location);
+  return session.logSourceLocation(message.params.callFrames[0].location);
 }