DevTools: Make item info follow the mouse on the flame chart.

third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js

 /**
  * Copyright (C) 2013 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 673 matching lines @@
 
         if (!this._enabled())
             return;
 
         if (this._isDragging)
             return;
 
         var inDividersBar = event.offsetY < WebInspector.FlameChart.DividersBarHeight;
         this._highlightedMarkerIndex = inDividersBar ? this._markerIndexAtPosition(event.offsetX) : -1;
         this._updateMarkerHighlight();
+        this._entryInfo.style.left = event.offsetX + "px";
+        this._entryInfo.style.top = event.offsetY + "px";
 
         this._highlightEntry(this._coordinatesToEntryIndex(event.offsetX, event.offsetY));
     },
 
     _onMouseOut: function()
     {
         this._highlightEntry(-1);
     },
 
     /**
@@ skipping 835 matching lines @@
         this.update();
     },
 
     _enabled: function()
     {
         return this._rawTimelineDataLength !== 0;
     },
 
     __proto__: WebInspector.HBox.prototype
 }