[css-align] Check runtime flags for align-items 'auto' value resolution

third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp

 /*
  * Copyright (C) 2004 Zack Rusin <zack@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007 Nicholas Shanks <webkit@nickshanks.com>
  * Copyright (C) 2011 Sencha, Inc. All rights reserved.
  * Copyright (C) 2015 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ skipping 429 matching lines @@
 
     return CSSReflectValue::create(direction, offset, valueForNinePieceImage(reflection->mask(), style));
 }
 
 static CSSValueList* valueForItemPositionWithOverflowAlignment(const StyleSelfAlignmentData& data)
 {
     CSSValueList* result = CSSValueList::createSpaceSeparated();
     if (data.positionType() == LegacyPosition)
         result->append(*CSSPrimitiveValue::createIdentifier(CSSValueLegacy));
     // To avoid needing to copy the RareNonInheritedData, we repurpose the 'auto' flag to not just mean 'auto' prior to running the StyleAdjuster but also mean 'normal' after running it.
-    result->append(*CSSPrimitiveValue::create(data.position() == ItemPositionAuto ? ItemPositionNormal : data.position()));
+    result->append(*CSSPrimitiveValue::create(data.position() == ItemPositionAuto ? ComputedStyle::initialDefaultAlignment().position() : data.position()));
     if (data.position() >= ItemPositionCenter && data.overflow() != OverflowAlignmentDefault)
         result->append(*CSSPrimitiveValue::create(data.overflow()));
     ASSERT(result->length() <= 2);
     return result;
 }
 
 static CSSValueList* valuesForGridShorthand(const StylePropertyShorthand& shorthand, const ComputedStyle& style, const LayoutObject* layoutObject, Node* styledNode, bool allowVisitedStyle)
 {
     CSSValueList* list = CSSValueList::createSlashSeparated();
     for (size_t i = 0; i < shorthand.length(); ++i) {
@@ skipping 2541 matching lines @@
     case CSSPropertyAll:
         return nullptr;
     default:
         break;
     }
     ASSERT_NOT_REACHED();
     return nullptr;
 }
 
 } // namespace blink