Revert of Catch up the spec update in CSS Rhythmic Sizing

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

Index: third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
diff --git a/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp b/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
index 5b6fea71243dac070b684e0c90a74b5024d99f54..f93e329d6930aba981aa31fad2d7a673f1b4228a 100644
--- a/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
+++ b/third_party/WebKit/Source/core/css/ComputedStyleCSSValueMapping.cpp
@@ -2532,8 +2532,6 @@
               : CSSPrimitiveValue::UnitType::Number);
     case CSSPropertyLineHeight:
       return valueForLineHeight(style);
-    case CSSPropertyLineHeightStep:
-      return zoomAdjustedPixelValue(style.lineHeightStep(), style);
     case CSSPropertyListStyleImage:
       if (style.listStyleImage())
         return style.listStyleImage()->computedCSSValue();
@@ -3648,6 +3646,18 @@
       ASSERT(list->length());
       return list;
     }
+    case CSSPropertySnapHeight: {
+      if (!style.snapHeightUnit())
+        return CSSPrimitiveValue::create(0,
+                                         CSSPrimitiveValue::UnitType::Pixels);
+      CSSValueList* list = CSSValueList::createSpaceSeparated();
+      list->append(*CSSPrimitiveValue::create(
+          style.snapHeightUnit(), CSSPrimitiveValue::UnitType::Pixels));
+      if (style.snapHeightPosition())
+        list->append(*CSSPrimitiveValue::create(
+            style.snapHeightPosition(), CSSPrimitiveValue::UnitType::Integer));
+      return list;
+    }
     case CSSPropertyVariable:
       // Variables are retrieved via get(AtomicString).
       ASSERT_NOT_REACHED();