Initialize min/max record time to 0 instead of -1 or null

Source/devtools/front_end/timeline/TimelineFlameChart.js

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 113 matching lines @@
          * @type {?WebInspector.FlameChart.TimelineData}
          */
         this._timelineData = {
             entryLevels: [],
             entryTotalTimes: [],
             entryStartTimes: []
         };
 
         this._records = [];
         this._entryThreadDepths = {};
-        this._minimumBoundary = Math.max(0, this._model.minimumRecordTime());
+        this._minimumBoundary = this._model.minimumRecordTime();
 
         var cpuThreadRecordPayload = { type: WebInspector.TimelineModel.RecordType.Program };
         this._cpuThreadRecord = new WebInspector.TimelineModel.RecordImpl(this._model, /** @type {!TimelineAgent.TimelineEvent} */ (cpuThreadRecordPayload), null);
         this._pushRecord(this._cpuThreadRecord, 0, this.minimumBoundary(), Math.max(this._model.maximumRecordTime(), this.totalTime() + this.minimumBoundary()));
 
         this._gpuThreadRecord = null;
 
         var records = this._model.records();
         for (var i = 0; i < records.length; ++i) {
             var record = records[i];
@@ skipping 397 matching lines @@
         /**
          * @type {?WebInspector.FlameChart.TimelineData}
          */
         this._timelineData = {
             entryLevels: [],
             entryTotalTimes: [],
             entryStartTimes: []
         };
 
         this._currentLevel = 0;
-        this._minimumBoundary = this._model.minimumRecordTime() || 0;
-        this._timeSpan = Math.max((this._model.maximumRecordTime() || 0) - this._minimumBoundary, 1000000);
+        this._minimumBoundary = this._model.minimumRecordTime();
+        this._timeSpan = Math.max(this._model.maximumRecordTime() - this._minimumBoundary, 1000);
         this._appendHeaderRecord("CPU");
         var events = this._model.mainThreadEvents();
         var maxStackDepth = 0;
         for (var eventIndex = 0; eventIndex < events.length; ++eventIndex) {
             var event = events[eventIndex];
             var category = event.category;
             if (category !== "disabled-by-default-devtools.timeline" && category !== "devtools")
                 continue;
             if (event.duration || event.phase === WebInspector.TracingModel.Phase.Instant) {
                 this._appendEvent(event);
@@ skipping 407 matching lines @@
      * @param {number} entryIndex
      * @return {?WebInspector.TimelineSelection}
      */
     createSelection: function(entryIndex) { },
     /**
      * @param {?WebInspector.TimelineSelection} selection
      * @return {number}
      */
     entryIndexForSelection: function(selection) { }
 }