Add ColorProperty, see phetsims/axon#221

js/util/ColorProperty.js

@@ -0,0 +1,32 @@
+// Copyright 2020, University of Colorado Boulder
+
+import Property from '../../../axon/js/Property.js';
+import merge from '../../../phet-core/js/merge.js';
+import Color from './Color.js';
+import scenery from '../scenery.js';
+
+/**
+ * Convenience type for creating Property<Color>
+ *
+ * @author Sam Reid (PhET Interactive Simulations)
+ */
+class ColorProperty extends Property {
+
+  constructor( color, options ) {
+
+    // client cannot specify superclass options that are controlled by this type
+    if ( options ) {
+      assert && assert( !options.hasOwnProperty( 'valueType' ), 'ColorProperty sets valueType' );
+      assert && assert( !options.hasOwnProperty( 'phetioType' ), 'ColorProperty sets phetioType' );
+    }
+
+    options = merge( {
+      valueType: Color,
+      phetioType: Property.PropertyIO( Color.ColorIO )
+    }, options );
+    super( color, options );
+  }
+}
+
+scenery.register( 'ColorProperty', ColorProperty );
+export default ColorProperty;