Add CSS Color types (#760)

Author: saschanaz

baselines/dom.generated.d.ts

@@ -2825,7 +2825,7 @@ interface CSSStyleDeclaration {
     clip: string;
     clipPath: string;
     clipRule: string;
-    color: string | null;
+    color: string;
     colorInterpolation: string;
     colorInterpolationFilters: string;
     columnCount: string;
@@ -3002,7 +3002,7 @@ interface CSSStyleDeclaration {
     msWrapThrough: string;
     objectFit: string;
     objectPosition: string;
-    opacity: string | null;
+    opacity: string;
     order: string;
     orphans: string;
     outline: string;

inputfiles/idl/CSS Color.widl

@@ -0,0 +1,4 @@
+partial interface CSSStyleDeclaration {
+  [CEReactions] attribute [TreatNullAs=EmptyString] CSSOMString color;
+  [CEReactions] attribute [TreatNullAs=EmptyString] CSSOMString opacity;
+};

inputfiles/idlSources.json

@@ -32,6 +32,10 @@
         "url": "https://www.w3.org/TR/css-align-3/",
         "title": "CSS Box Alignment"
     },
+    {
+        "url": "https://www.w3.org/TR/css-color-3/",
+        "title": "CSS Color"
+    },
     {
         "url": "https://www.w3.org/TR/fill-stroke-3/",
         "title": "CSS Fill and Stroke"