ntp4: hack around skia gradient brokenness.

chrome/browser/resources/ntp4/tile_page.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 cr.define('ntp4', function() {
   'use strict';
 
   // We can't pass the currently dragging tile via dataTransfer because of
   // http://crbug.com/31037
   var currentlyDraggingTile = null;
@@ skipping 705 matching lines @@
      * as they enter or exit the grid.
      * @private
      */
     updateMask_: function() {
       if (!this.isCurrentDragTarget) {
         this.tileGrid_.style.WebkitMaskBoxImage = '';
         return;
       }
 
       var leftMargin = this.layoutValues_.leftMargin;
-      var fadeDistance = Math.min(leftMargin, 20);
+      // The fade distance is the space between tiles.
+      var fadeDistance = (this.gridValues_.tileSpacingFraction *
+          this.layoutValues_.tileWidth);
+      fadeDistance = Math.min(leftMargin, fadeDistance);
+      // On Skia we don't use any fade because it works very poorly. See
+      // http://crbug.com/99373
+      if (!cr.isMac)

[Dan Beam, 2011/10/07 20:05:42]

I still think you should mention in the above comment that Mac doesn't use Skia,
otherwise the following conditional isn't as clear.

+        fadeDistance = 1;
       var gradient =
           '-webkit-linear-gradient(left,' +
               'transparent, ' +
               'transparent ' + (leftMargin - fadeDistance) + 'px, ' +
               'black ' + leftMargin + 'px, ' +
               'black ' + (this.tileGrid_.clientWidth - leftMargin) + 'px, ' +
               'transparent ' + (this.tileGrid_.clientWidth - leftMargin +
                                 fadeDistance) + 'px, ' +
               'transparent)';
       this.tileGrid_.style.WebkitMaskBoxImage = gradient;
@@ skipping 352 matching lines @@
       assert(false);
     },
   };
 
   return {
     getCurrentlyDraggingTile: getCurrentlyDraggingTile,
     setCurrentDropEffect: setCurrentDropEffect,
     TilePage: TilePage,
   };
 });