Move the dom directory from web-platform-tests/ to wpt/.

third_party/WebKit/LayoutTests/imported/wpt/dom/nodes/DOMImplementation-createHTMLDocument.js

 function createHTMLDocuments(checkDoc) {
   var tests = [
     ["", "", ""],
     [null, "null", "null"],
     [undefined, undefined, ""],
     ["foo  bar baz", "foo  bar baz", "foo bar baz"],
     ["foo\t\tbar baz", "foo\t\tbar baz", "foo bar baz"],
     ["foo\n\nbar baz", "foo\n\nbar baz", "foo bar baz"],
     ["foo\f\fbar baz", "foo\f\fbar baz", "foo bar baz"],
     ["foo\r\rbar baz", "foo\r\rbar baz", "foo bar baz"],
   ]
 
   tests.forEach(function(t, i) {
     var title = t[0], expectedtitle = t[1], normalizedtitle = t[2]
     test(function() {
       var doc = document.implementation.createHTMLDocument(title);
       checkDoc(doc, expectedtitle, normalizedtitle)
     }, "createHTMLDocument test " + i + ": " + t.map(function(el) { return format_value(el) }))
   })
 
   test(function() {
     var doc = document.implementation.createHTMLDocument();
     checkDoc(doc, undefined, "")
   }, "Missing title argument");
 }