[inspector] better isArrayLike for injected-script-source.js

test/inspector/protocol-test.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 = {};
 InspectorTest._dispatchTable = new Map();
 InspectorTest._requestId = 0;
 InspectorTest._dumpInspectorProtocolMessages = false;
 InspectorTest._eventHandler = {};
 InspectorTest._commandsForLogging = new Set();
@@ skipping 326 matching lines @@
     defineProperty(ObjectPrototype, '${getter}', {
       set() { debugger; throw 42; }, get() { debugger; throw 42; },
       __proto__: null
     });
   `).join('\n') + '})();';
   InspectorTest.addScript(scriptSource);
 
   if (debug) {
     InspectorTest.log('WARNING: InspectorTest.setupInjectedScriptEnvironment with debug flag for debugging only and should not be landed.');
     InspectorTest.log('WARNING: run test with --expose-inspector-scripts flag to get more details.');
+    InspectorTest.log('WARNING: you can additionally comment rjsmin in xxd.py to get unminified injected-script-source.js.');
     InspectorTest.setupScriptMap();
     Protocol.Debugger.enable();
     Protocol.Debugger.onPaused(message => {
       let callFrames = message.params.callFrames;
       InspectorTest.logSourceLocations(callFrames.map(frame => frame.location));
     })
   }
 }