Implement parseShorthand API for shorthand properties, "overflow", "font" and "font-variant"

third_party/WebKit/Source/core/css/CSSProperties.json5

 {
 // This file specifies all the CSS properties we support and the necessary
 // information for our code generation. The various supported arguments
 // are described below with example usage
 
   parameters: {
     // - alias_for: "other-property"
     // Properties specifying alias_for should be virtually identical to the
     // properties they alias. Minor parsing differences are allowed as long as
     // the CSSValues created are of the same format of the aliased property.
@@ skipping 3617 matching lines @@
       api_class: true,
       api_methods: ["parseShorthand"],
     },
     {
       name: "flex-flow",
       longhands: "flex-direction;flex-wrap",
     },
     {
       name: "font",
       longhands: "font-style;font-variant-ligatures;font-variant-caps;font-variant-numeric;font-weight;font-stretch;font-size;line-height;font-family",
+      api_class: true,
+      api_methods: ["parseShorthand"],
     },
     {
       name: "font-variant",
       longhands: "font-variant-ligatures;font-variant-caps;font-variant-numeric",
+      api_class: true,
+      api_methods: ["parseShorthand"],
       is_descriptor: true,
     },
     {
       name: "grid",
       longhands: "grid-template-rows;grid-template-columns;grid-template-areas;grid-auto-flow;grid-auto-rows;grid-auto-columns;grid-column-gap;grid-row-gap",
       runtime_flag: "CSSGridLayout",
     },
     {
       name: "place-content",
       longhands: "align-content;justify-content",
@@ skipping 50 matching lines @@
       name: "offset",
       longhands: "offset-position;offset-path;offset-distance;offset-rotate;offset-anchor",
     },
     {
       name: "outline",
       longhands: "outline-color;outline-style;outline-width",
     },
     {
       name: "overflow",
       longhands: "overflow-x;overflow-y",
+      api_class: true,
+      api_methods: ["parseShorthand"],
     },
     {
       name: "padding",
       longhands: "padding-top;padding-right;padding-bottom;padding-left",
     },
     {
       name: "page-break-after",
       longhands: "break-after",
     },
     {
@@ skipping 377 matching lines @@
     {
       name: "-webkit-transition-timing-function",
       alias_for: "transition-timing-function",
     },
     {
       name: "-webkit-user-select",
       alias_for: "user-select",
     },
   ],
 }