[css-grid] Implement fit-content track size

third_party/WebKit/Source/core/css/resolver/StyleBuilderConverter.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  *     * 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
  * copyright notice, this list of conditions and the following disclaimer
  * in the documentation and/or other materials provided with the
  * distribution.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 521 matching lines @@
         position.setExplicitPosition(gridLineNumber, gridLineName);
 
     return position;
 }
 
 GridTrackSize StyleBuilderConverter::convertGridTrackSize(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPrimitiveValue())
         return GridTrackSize(convertGridTrackBreadth(state, toCSSPrimitiveValue(value)));
 
-    const CSSFunctionValue& minmaxFunction = toCSSFunctionValue(value);
-    ASSERT_WITH_SECURITY_IMPLICATION(minmaxFunction.length() == 2);
-    GridLength minTrackBreadth(convertGridTrackBreadth(state, toCSSPrimitiveValue(minmaxFunction.item(0))));
-    GridLength maxTrackBreadth(convertGridTrackBreadth(state, toCSSPrimitiveValue(minmaxFunction.item(1))));
+    auto& function = toCSSFunctionValue(value);
+    if (function.functionType() == CSSValueFitContent) {
+        SECURITY_DCHECK(function.length() == 1);
+        return GridTrackSize(convertGridTrackBreadth(state, toCSSPrimitiveValue(function.item(0))), FitContentTrackSizing);
+    }
+
+    SECURITY_DCHECK(function.length() == 2);
+    GridLength minTrackBreadth(convertGridTrackBreadth(state, toCSSPrimitiveValue(function.item(0))));
+    GridLength maxTrackBreadth(convertGridTrackBreadth(state, toCSSPrimitiveValue(function.item(1))));
     return GridTrackSize(minTrackBreadth, maxTrackBreadth);
 }
 
 static void convertGridLineNamesList(const CSSValue& value, size_t currentNamedGridLine, NamedGridLinesMap& namedGridLines, OrderedNamedGridLines& orderedNamedGridLines)
 {
     ASSERT(value.isGridLineNamesValue());
 
     for (auto& namedGridLineValue : toCSSValueList(value)) {
         String namedGridLine = toCSSCustomIdentValue(*namedGridLineValue).value();
         NamedGridLinesMap::AddResult result = namedGridLines.add(namedGridLine, Vector<size_t>());
@@ skipping 534 matching lines @@
 
 PassRefPtr<StylePath> StyleBuilderConverter::convertPathOrNone(StyleResolverState& state, const CSSValue& value)
 {
     if (value.isPathValue())
         return toCSSPathValue(value).stylePath();
     ASSERT(value.isPrimitiveValue() && toCSSPrimitiveValue(value).getValueID() == CSSValueNone);
     return nullptr;
 }
 
 } // namespace blink