Update "contain" property to accept "inline-size"

Closes #370

Author: Seirdy

org/w3c/css/properties/css3/CssContain.java

@@ -34,7 +34,13 @@ public class CssContain extends org.w3c.css.properties.css.CssContain {
             allowed_single_values[i++] = CssIdent.getIdent(s);
         }
         // "style" added as of css-contain-2 but at-risk
-        String[] _allowed_multiple_values = {"size", "layout", "paint", "style"};
+        String[] _allowed_multiple_values = {
+            "size",
+            "inline-size",
+            "layout",
+            "paint",
+            "style",
+        };
         i = 0;
         allowed_multiple_values = new CssIdent[_allowed_multiple_values.length];
         for (String s : _allowed_multiple_values) {