Only default to transition shorthand if all 4 values are set

Source/core/css/StylePropertySerializer.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 235 matching lines @@
 
     ASSERT(!numDecls ^ !result.isEmpty());
     return result.toString();
 }
 
 String StylePropertySerializer::getPropertyValue(CSSPropertyID propertyID) const
 {
     // Shorthand and 4-values properties
     switch (propertyID) {
     case CSSPropertyAnimation:
-        return getLayeredShorthandValue(animationShorthand());
+        return getLayeredShorthandValue(animationShorthand(), true);
     case CSSPropertyBorderSpacing:
         return borderSpacingValue(borderSpacingShorthand());
     case CSSPropertyBackgroundPosition:
         return getLayeredShorthandValue(backgroundPositionShorthand());
     case CSSPropertyBackgroundRepeat:
         return backgroundRepeatPropertyValue();
     case CSSPropertyBackground:
         return getLayeredShorthandValue(backgroundShorthand());
     case CSSPropertyBorder:
         return borderPropertyValue(OmitUncommonValues);
@@ skipping 31 matching lines @@
         return fontValue();
     case CSSPropertyMargin:
         return get4Values(marginShorthand());
     case CSSPropertyWebkitMarginCollapse:
         return getShorthandValue(webkitMarginCollapseShorthand());
     case CSSPropertyOverflow:
         return getCommonValue(overflowShorthand());
     case CSSPropertyPadding:
         return get4Values(paddingShorthand());
     case CSSPropertyTransition:
-        return getLayeredShorthandValue(transitionShorthand());
+        return getLayeredShorthandValue(transitionShorthand(), true);
     case CSSPropertyListStyle:
         return getShorthandValue(listStyleShorthand());
     case CSSPropertyWebkitMaskPosition:
         return getLayeredShorthandValue(webkitMaskPositionShorthand());
     case CSSPropertyWebkitMaskRepeat:
         return getLayeredShorthandValue(webkitMaskRepeatShorthand());
     case CSSPropertyWebkitMask:
         return getLayeredShorthandValue(webkitMaskShorthand());
     case CSSPropertyWebkitTextEmphasis:
         return getShorthandValue(webkitTextEmphasisShorthand());
     case CSSPropertyWebkitTextStroke:
         return getShorthandValue(webkitTextStrokeShorthand());
     case CSSPropertyTransformOrigin:
     case CSSPropertyWebkitTransformOrigin:
         return getShorthandValue(webkitTransformOriginShorthand());
     case CSSPropertyWebkitTransition:
-        return getLayeredShorthandValue(webkitTransitionShorthand());
+        return getLayeredShorthandValue(webkitTransitionShorthand(), true);
     case CSSPropertyWebkitAnimation:
-        return getLayeredShorthandValue(webkitAnimationShorthand());
+        return getLayeredShorthandValue(webkitAnimationShorthand(), true);
     case CSSPropertyMarker: {
         RefPtrWillBeRawPtr<CSSValue> value = m_propertySet.getPropertyCSSValue(CSSPropertyMarkerStart);
         if (value)
             return value->cssText();
         return String();
     }
     case CSSPropertyBorderRadius:
         return get4Values(borderRadiusShorthand());
     default:
         return String();
@@ skipping 131 matching lines @@
         result.append(' ');
         result.append(bottom.value()->cssText());
     }
     if (showLeft) {
         result.append(' ');
         result.append(left.value()->cssText());
     }
     return result.toString();
 }
 
-String StylePropertySerializer::getLayeredShorthandValue(const StylePropertyShorthand& shorthand) const
+String StylePropertySerializer::getLayeredShorthandValue(const StylePropertyShorthand& shorthand, bool checkShorthandAvailable) const
 {
     StringBuilder result;
 
     const unsigned size = shorthand.length();
     // Begin by collecting the properties into an array.
     WillBeHeapVector<RefPtrWillBeMember<CSSValue> > values(size);
     size_t numLayers = 0;
 
     for (unsigned i = 0; i < size; ++i) {
         values[i] = m_propertySet.getPropertyCSSValue(shorthand.properties()[i]);
         if (values[i]) {
             if (values[i]->isBaseValueList()) {
                 CSSValueList* valueList = toCSSValueList(values[i].get());
                 numLayers = std::max(valueList->length(), numLayers);
             } else {
                 numLayers = std::max<size_t>(1U, numLayers);
             }
+        } else if (checkShorthandAvailable) {
+            return String();
         }
     }
 
+
     String commonValue;
     bool commonValueInitialized = false;
 
     // Now stitch the properties together. Implicit initial values are flagged as such and
     // can safely be omitted.
     for (size_t i = 0; i < numLayers; i++) {
         StringBuilder layerResult;
         bool useRepeatXShorthand = false;
         bool useRepeatYShorthand = false;
         bool useSingleWordShorthand = false;
@@ skipping 362 matching lines @@
             isInitialValue = false;
         if (!value->isInheritedValue())
             isInheritedValue = false;
         if (isImportant != m_propertySet.propertyIsImportant(shorthand.properties()[i]))
             return false;
     }
     return isInitialValue || isInheritedValue;
 }
 
 }