[css-grid] Implement grid gutters

Source/core/css/parser/CSSParserFastPaths.cpp

 // Copyright 2014 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.
 
 #include "config.h"
 #include "core/css/parser/CSSParserFastPaths.h"
 
 #include "core/StylePropertyShorthand.h"
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSValuePool.h"
 #include "core/css/parser/CSSParserIdioms.h"
 #include "core/css/parser/CSSParserString.h"
 #include "core/css/parser/CSSPropertyParser.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "platform/RuntimeEnabledFeatures.h"
 
 namespace blink {
 
 static inline bool isSimpleLengthPropertyID(CSSPropertyID propertyId, bool& acceptsNegativeNumbers)
 {
     switch (propertyId) {
     case CSSPropertyFontSize:
+    case CSSPropertyGridColumnGap:
+    case CSSPropertyGridRowGap:
     case CSSPropertyHeight:
     case CSSPropertyWidth:
     case CSSPropertyMinHeight:
     case CSSPropertyMinWidth:
     case CSSPropertyPaddingBottom:
     case CSSPropertyPaddingLeft:
     case CSSPropertyPaddingRight:
     case CSSPropertyPaddingTop:
     case CSSPropertyWebkitLogicalWidth:
     case CSSPropertyWebkitLogicalHeight:
@@ skipping 972 matching lines @@
     if (isColorPropertyID(propertyID))
         return parseColor(string, parserMode);
     if (RefPtrWillBeRawPtr<CSSValue> keyword = parseKeywordValue(propertyID, string))
         return keyword.release();
     if (RefPtrWillBeRawPtr<CSSValue> transform = parseSimpleTransform(propertyID, string))
         return transform.release();
     return nullptr;
 }
 
 } // namespace blink