DevTools: Grey out outside parts of selection window on timeline overview.

third_party/WebKit/Source/devtools/front_end/timeline/TimelineView.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2012 Intel 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.
@@ skipping 715 matching lines @@
      * @param {!Event} e
      */
     _mouseMove: function(e)
     {
         var rowElement = e.target.enclosingNodeOrSelfWithClass("timeline-tree-item");
         if (!this._highlightQuad(rowElement))
             this._hideQuadHighlight();
 
         var taskBarElement = e.target.enclosingNodeOrSelfWithClass("timeline-graph-bar");
         if (taskBarElement && taskBarElement._tasksInfo) {
-            var offset = taskBarElement.offsetLeft;
-            this._timelineGrid.showCurtains(offset >= 0 ? offset : 0, taskBarElement.offsetWidth);
+            var parentWidth = taskBarElement.parentElement.offsetWidth;
+            var offset = Math.max(0, taskBarElement.offsetLeft);
+            var width = taskBarElement.offsetWidth;
+            this._timelineGrid.showCurtains(offset / parentWidth, (offset + width) / parentWidth);
         } else
             this._timelineGrid.hideCurtains();
     },
 
     /**
      * @param {!Event} event
      */
     _keyDown: function(event)
     {
         if (!this._lastSelectedRecord || event.shiftKey || event.metaKey || event.ctrlKey)
@@ skipping 554 matching lines @@
         } else {
             this._element.classList.add("hidden");
         }
     },
 
     _dispose: function()
     {
         this._element.remove();
     }
 }