[CSS Grid Layout] Rename grid placement properties

Source/core/css/CSSComputedStyleDeclaration.cpp

Index: Source/core/css/CSSComputedStyleDeclaration.cpp
diff --git a/Source/core/css/CSSComputedStyleDeclaration.cpp b/Source/core/css/CSSComputedStyleDeclaration.cpp
index 64defa56deadd233156d5206a76a7e3b2f516fb8..d81f2f4b4eaaf75948ea6bafcf657065e3cda2f3 100644
--- a/Source/core/css/CSSComputedStyleDeclaration.cpp
+++ b/Source/core/css/CSSComputedStyleDeclaration.cpp
@@ -259,12 +259,12 @@ static const CSSPropertyID staticComputableProperties[] = {
     CSSPropertyGridAutoColumns,
     CSSPropertyGridAutoFlow,
     CSSPropertyGridAutoRows,
+    CSSPropertyGridColumnEnd,
+    CSSPropertyGridColumnStart,
     CSSPropertyGridColumns,
+    CSSPropertyGridRowEnd,
+    CSSPropertyGridRowStart,
     CSSPropertyGridRows,
-    CSSPropertyGridStart,
-    CSSPropertyGridEnd,
-    CSSPropertyGridBefore,
-    CSSPropertyGridAfter,
     CSSPropertyWebkitHighlight,
     CSSPropertyWebkitHyphenateCharacter,
     CSSPropertyWebkitHyphenateLimitAfter,
@@ -1924,14 +1924,14 @@ PassRefPtr<CSSValue> CSSComputedStyleDeclaration::getPropertyCSSValue(CSSPropert
         case CSSPropertyGridRows:
             return valueForGridTrackList(style->gridRows(), style->namedGridRowLines(), style.get(), m_node->document()->renderView());
 
-        case CSSPropertyGridStart:
-            return valueForGridPosition(style->gridStart());
-        case CSSPropertyGridEnd:
-            return valueForGridPosition(style->gridEnd());
-        case CSSPropertyGridBefore:
-            return valueForGridPosition(style->gridBefore());
-        case CSSPropertyGridAfter:
-            return valueForGridPosition(style->gridAfter());
+        case CSSPropertyGridColumnStart:
+            return valueForGridPosition(style->gridColumnStart());
+        case CSSPropertyGridColumnEnd:
+            return valueForGridPosition(style->gridColumnEnd());
+        case CSSPropertyGridRowStart:
+            return valueForGridPosition(style->gridRowStart());
+        case CSSPropertyGridRowEnd:
+            return valueForGridPosition(style->gridRowEnd());
         case CSSPropertyGridColumn:
             return getCSSPropertyValuesForGridShorthand(gridColumnShorthand());
         case CSSPropertyGridRow: