Add CSS parsing support for the scroll-blocks-on property (in place of touch-action-delay)

Source/core/css/parser/CSSPropertyParser.cpp

Index: Source/core/css/parser/CSSPropertyParser.cpp
diff --git a/Source/core/css/parser/CSSPropertyParser.cpp b/Source/core/css/parser/CSSPropertyParser.cpp
index 043bb21d8ca104410b39cabc06511c0877bf3bdb..0fcd2821b25b3927a8482fe3907c906df487c4cd 100644
--- a/Source/core/css/parser/CSSPropertyParser.cpp
+++ b/Source/core/css/parser/CSSPropertyParser.cpp
@@ -1483,6 +1483,10 @@ bool CSSPropertyParser::parseValue(CSSPropertyID propId, bool important)
         parsedValue = parseTouchAction();
         break;
 
+    case CSSPropertyScrollBlocksOn:
+        parsedValue = parseScrollBlocksOn();
+        break;
+
     case CSSPropertyAlignSelf:
         ASSERT(RuntimeEnabledFeatures::cssGridLayoutEnabled());
         return parseItemPositionOverflowPosition(propId, important);
@@ -7385,6 +7389,39 @@ PassRefPtrWillBeRawPtr<CSSValue> CSSPropertyParser::parseTouchAction()
     return nullptr;
 }
 
+PassRefPtrWillBeRawPtr<CSSValue> CSSPropertyParser::parseScrollBlocksOn()
+{
+    CSSParserValue* value = m_valueList->current();
+    RefPtrWillBeRawPtr<CSSValueList> list = CSSValueList::createSpaceSeparated();
+    if (m_valueList->size() == 1 && value && (value->id == CSSValueNone)) {

[Timothy Loh, 2014/11/14 22:06:41]

I'm pretty sure we don't need to check the size (checked after the gigantic
switch) or that value is non-null (checked before the gigantic switch). Also I
think we can just return a CSSPrimitiveValue in this case instead of wrapping in
a list.

[Rick Byers, 2014/11/18 03:03:08]

Done.

+        list->append(cssValuePool().createIdentifierValue(CSSValueNone));
+        m_valueList->next();
+        return list.release();
+    }
+
+    while (value) {
+        switch (value->id) {
+        case CSSValueStartTouch:
+        case CSSValueWheelEvent:
+        case CSSValueScrollEvent: {
+            RefPtrWillBeRawPtr<CSSValue> flagValue = cssValuePool().createIdentifierValue(value->id);
+            if (list->hasValue(flagValue.get()))
+                return nullptr;
+            list->append(flagValue.release());
+            break;
+        }
+        default:
+            return nullptr;
+        }
+        value = m_valueList->next();
+    }
+
+    if (list->length())

[Timothy Loh, 2014/11/14 22:06:41]

Since value is never null when we get into this function, the list will never be
empty. Maybe better to ASSERT we're not empty.

[Rick Byers, 2014/11/18 03:03:08]

Done.

+        return list.release();
+
+    return nullptr;
+}
+
 void CSSPropertyParser::addTextDecorationProperty(CSSPropertyID propId, PassRefPtrWillBeRawPtr<CSSValue> value, bool important)
 {
     // The text-decoration-line property takes priority over text-decoration, unless the latter has important priority set.