DevTools: Make sure flamechart vertical scroll stays within the height of contents.

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 1932 matching lines @@
         this._timeToPixel = totalPixels / this._totalTime;
         this._pixelToTime = this._totalTime / totalPixels;
 
         this._updateScrollBar();
     },
 
     _updateHeight: function()
     {
         this._totalHeight = this._levelToHeight(this._dataProvider.maxStackDepth());
         this._vScrollContent.style.height = this._totalHeight + "px";
+        if (this._scrollTop + this._offsetHeight > this._totalHeight) {
+            this._scrollTop = Math.max(0, this._totalHeight - this._offsetHeight);
+            this._vScrollElement.scrollTop = this._scrollTop;
+        }
     },
 
     onResize: function()
     {
         this._updateScrollBar();
         this._updateContentElementSize();
         this.scheduleUpdate();
     },
 
     _updateScrollBar: function()
@@ skipping 52 matching lines @@
         this.update();
     },
 
     _enabled: function()
     {
         return this._rawTimelineDataLength !== 0;
     },
 
     __proto__: WebInspector.HBox.prototype
 }