Patched display of XML to match ART.

Change:
.cm-s-default .cm-comment {color: #a50;}
.cm-s-default .cm-string {color: #a11;}

To:
.cm-s-default .cm-comment {color: grey;}
.cm-s-default .cm-string {color: orange;}

And:
.cm-s-default .cm-tag {color: #170;}
.cm-s-default .cm-attribute {color: #00c;}

To:
.cm-s-default .cm-tag {color: blue;}
.cm-s-default .cm-attribute {color: green;}