Add media element attributes

Fixes #1124.

I didn't add `volume` because it requires more complicated logic to control properly and I didn't add `paused` because to set it we need to call play() or pause() -- perhaps a mutation method is appropriate.

src/browser/dom/DefaultDOMPropertyConfig.js

@@ -59,6 +59,7 @@ var DefaultDOMPropertyConfig = {
     contentEditable: null,
     contextMenu: MUST_USE_ATTRIBUTE,
     controls: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
+    crossOrigin: null,
     data: null, // For `<object />` acts as `src`.
     dateTime: MUST_USE_ATTRIBUTE,
     defer: HAS_BOOLEAN_VALUE,
@@ -82,9 +83,11 @@ var DefaultDOMPropertyConfig = {
     loop: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
     max: null,
     maxLength: MUST_USE_ATTRIBUTE,
+    mediaGroup: null,
     method: null,
     min: null,
     multiple: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
+    muted: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
     name: null,
     noValidate: HAS_BOOLEAN_VALUE,
     pattern: null,