Implements CSSPropertyAPI for the scroll-snap-coordinate property.

third_party/WebKit/Source/core/css/properties/CSSPropertyAPIScrollSnapCoordinate.cpp

Index: third_party/WebKit/Source/core/css/properties/CSSPropertyAPIScrollSnapCoordinate.cpp
diff --git a/third_party/WebKit/Source/core/css/properties/CSSPropertyAPIScrollSnapCoordinate.cpp b/third_party/WebKit/Source/core/css/properties/CSSPropertyAPIScrollSnapCoordinate.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..286856fe6c0ecb28b245ab7b2c22a9cf694170e3
--- /dev/null
+++ b/third_party/WebKit/Source/core/css/properties/CSSPropertyAPIScrollSnapCoordinate.cpp
@@ -0,0 +1,35 @@
+// Copyright 2017 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 "core/css/properties/CSSPropertyAPIScrollSnapCoordinate.h"
+
+#include "core/css/CSSValueList.h"
+#include "core/css/CSSValuePair.h"
+#include "core/css/parser/CSSParserContext.h"
+#include "core/css/parser/CSSPropertyParserHelpers.h"
+
+namespace blink {
+
+static CSSValueList* consumePositionList(CSSParserTokenRange& range,
+                                         CSSParserMode cssParserMode) {
+  CSSValueList* positions = CSSValueList::createCommaSeparated();
+  do {
+    CSSValue* position = consumePosition(
+        range, cssParserMode, CSSPropertyParserHelpers::UnitlessQuirk::Forbid);
+    if (!position)
+      return nullptr;
+    positions->append(*position);
+  } while (CSSPropertyParserHelpers::consumeCommaIncludingWhitespace(range));
+  return positions;
+}
+
+const CSSValue* CSSPropertyAPIScrollSnapCoordinate::parseSingleValue(
+    CSSParserTokenRange& range,
+    const CSSParserContext& context) {
+  if (range.peek().id() == CSSValueNone)
+    return CSSPropertyParserHelpers::consumeIdent(range);
+  return consumePositionList(range, context.mode());
+}
+
+}  // namespace blink