[css-align] Adapt content-alignment properties to the new baseline syntax

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

Index: third_party/WebKit/Source/core/css/CSSContentDistributionValue.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSContentDistributionValue.cpp b/third_party/WebKit/Source/core/css/CSSContentDistributionValue.cpp
index 7b04ac0152fdc110c123dbc0f194fb5f82a36de4..ee7c4bcdd9bdbab2d4f03aeb750a4763d570a4f9 100644
--- a/third_party/WebKit/Source/core/css/CSSContentDistributionValue.cpp
+++ b/third_party/WebKit/Source/core/css/CSSContentDistributionValue.cpp
@@ -25,8 +25,17 @@ String CSSContentDistributionValue::customCSSText() const {
 
   if (m_distribution != CSSValueInvalid)
     list->append(*distribution());
-  if (m_position != CSSValueInvalid)
-    list->append(*position());
+  if (m_position != CSSValueInvalid) {
+    if (m_position == CSSValueFirstBaseline ||
+        m_position == CSSValueLastBaseline) {
+      CSSValueID preference =
+          m_position == CSSValueFirstBaseline ? CSSValueFirst : CSSValueLast;
+      list->append(*CSSIdentifierValue::create(preference));
+      list->append(*CSSIdentifierValue::create(CSSValueBaseline));
+    } else {
+      list->append(*position());
+    }
+  }
   if (m_overflow != CSSValueInvalid)
     list->append(*overflow());