Web Animations CSS: Handle border-spacing property

Source/core/animation/css/CSSAnimatableValueFactory.cpp

 /*
  * 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 192 matching lines @@
         // Should be interpolated as 'length', ie double?
         return createFromLength(style->paddingTop(), style);
     case CSSPropertyRight:
         return createFromLength(style->right(), style);
     case CSSPropertyTextDecorationColor:
         return createFromColor(property, style);
     case CSSPropertyTextIndent:
         return createFromLength(style->textIndent(), style);
     case CSSPropertyTop:
         return createFromLength(style->top(), style);
+    case CSSPropertyWebkitBorderHorizontalSpacing:
+        return createFromDouble(style->horizontalBorderSpacing());
+    case CSSPropertyWebkitBorderVerticalSpacing:
+        return createFromDouble(style->verticalBorderSpacing());
     case CSSPropertyWebkitColumnRuleColor:
         return createFromColor(property, style);
     case CSSPropertyWebkitColumnRuleWidth:
         return createFromDouble(style->columnRuleWidth());
     case CSSPropertyWebkitMaskBoxImageSource:
         return AnimatableImage::create(style->maskBoxImageSource());
     case CSSPropertyWebkitMaskImage:
         return AnimatableImage::create(style->maskImage());
     case CSSPropertyWebkitPerspectiveOriginX:
         return createFromLength(style->perspectiveOriginX(), style);
@@ skipping 20 matching lines @@
     case CSSPropertyZIndex:
         return createFromDouble(style->zIndex());
     default:
         RELEASE_ASSERT_WITH_MESSAGE(!CSSAnimations::isAnimatableProperty(property), "Web Animations not yet implemented: Create AnimatableValue from render style: %s", getPropertyNameString(property).utf8().data());
         ASSERT_NOT_REACHED();
         return 0;
     }
 }
 
 } // namespace WebCore