DevTools: merge TracingTimelineModel into TimelineModel

LayoutTests/inspector/tracing-test.js

 function initialize_TracingTest()
 {
 
 InspectorTest.preloadPanel("timeline");
 
 InspectorTest.tracingManager = function()
 {
     if (WebInspector.panels.timeline._tracingManager)
         return WebInspector.panels.timeline._tracingManager;
     if (!InspectorTest._tracingManager)
         InspectorTest._tracingManager = new WebInspector.TracingManager();
     return InspectorTest._tracingManager;
 }
 
 InspectorTest.tracingModel = function()
 {
     if (!InspectorTest._tracingModel)
         InspectorTest._tracingModel = new WebInspector.TracingModel();
     return InspectorTest._tracingModel;
 }
 
 InspectorTest.tracingTimelineModel = function()
 {
     if (!InspectorTest._tracingTimelineModel)
-        InspectorTest._tracingTimelineModel = new WebInspector.TracingTimelineModel(InspectorTest.tracingManager(), InspectorTest.tracingModel(), new WebInspector.TimelineRecordHiddenTypeFilter([]));
+        InspectorTest._tracingTimelineModel = new WebInspector.TimelineModel(InspectorTest.tracingManager(), InspectorTest.tracingModel(), new WebInspector.TimelineRecordHiddenTypeFilter([]));
     return InspectorTest._tracingTimelineModel;
 }
 
 InspectorTest.invokeWithTracing = function(functionName, callback, additionalCategories)
 {
     InspectorTest.tracingTimelineModel().addEventListener(WebInspector.TimelineModel.Events.RecordingStarted, onTracingStarted, this);
     var categories = "-*,disabled-by-default-devtools.timeline*";
     if (additionalCategories)
         categories += "," + additionalCategories;
     InspectorTest.tracingTimelineModel()._startRecordingWithCategories(categories);
@@ skipping 11 matching lines @@
     }
 
     function onTracingComplete(event)
     {
         InspectorTest.tracingTimelineModel().removeEventListener(WebInspector.TimelineModel.Events.RecordingStopped, onTracingComplete, this);
         callback();
     }
 }
 
 }