Implement runtime feature support for CSS Shorthands

Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl

Index: Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl
diff --git a/Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl b/Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl
index 8c8c16a843880559415389af8ba007b8442d9902..a491e03c0ad856c194d92b4328bffc89e886faa8 100644
--- a/Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl
+++ b/Source/core/scripts/templates/StylePropertyShorthand.cpp.tmpl
@@ -21,6 +21,7 @@
 
 #include "config.h"
 #include "StylePropertyShorthand.h"
+#include "RuntimeEnabledFeatures.h"
 
 #include "wtf/HashMap.h"
 #include "wtf/StdLibExtras.h"
@@ -44,15 +45,19 @@ const StylePropertyShorthand& {{ property.camel_case_name }}Shorthand()
 // Returns an empty list if the property is not a shorthand
 const StylePropertyShorthand& shorthandForProperty(CSSPropertyID propertyID)
 {
+    DEFINE_STATIC_LOCAL(StylePropertyShorthand, emptyShorthand, ());
     switch (propertyID) {
 {%- for property_id, property in properties.items() %}
     {%- if property.camel_case_name not in ["width", "height", "marker"] %}
         case {{ property_id }}:
+        {%- if property.runtime_conditional_getter %}
+            if (!RuntimeEnabledFeatures::{{ property.runtime_conditional_getter }}())
+                return emptyShorthand;
+        {%- endif %}
             return {{ property.camel_case_name }}Shorthand();
     {%- endif %}
 {%- endfor %}
     default: {
-        DEFINE_STATIC_LOCAL(StylePropertyShorthand, emptyShorthand, ());
         return emptyShorthand;
     }
     }