DOMTokenList: Update serialization algorithm on add()/remove()

third_party/WebKit/LayoutTests/fast/dom/HTMLElement/resources/class-list.js

 description('Tests the classList attribute and its properties.');
 
 var element;
 
 function createElement(className)
 {
     element = document.createElement('p');
     element.className = className;
 }
 
@@ skipping 31 matching lines @@
 shouldBeEqualToString('element.className', 'x');
 
 // http://simon.html5.org/test/html/dom/reflecting/DOMTokenList/getting/006.htm
 createElement('x');
 element.classList.add('x');
 shouldBeEqualToString('element.className', 'x');
 
 // http://simon.html5.org/test/html/dom/reflecting/DOMTokenList/getting/007.htm
 createElement('x  x');
 element.classList.add('x');
-shouldBeEqualToString('element.className', 'x  x');
+shouldBeEqualToString('element.className', 'x x');
 
 // http://simon.html5.org/test/html/dom/reflecting/DOMTokenList/getting/008.htm
 createElement('y');
 element.classList.add('x');
 shouldBeEqualToString('element.className', 'y x');
 
 // http://simon.html5.org/test/html/dom/reflecting/DOMTokenList/getting/009.htm
 createElement('');
 element.classList.remove('x');
 shouldBeEqualToString('element.className', '');
@@ skipping 50 matching lines @@
 
 
 debug('Testing add in presence of trailing white spaces.');
 
 createElement('x ');
 element.classList.add('y');
 shouldBeEqualToString('element.className', 'x y');
 
 createElement('x\t');
 element.classList.add('y');
-shouldBeEqualToString('element.className', 'x\ty');
+shouldBeEqualToString('element.className', 'x y');
 
 createElement(' ');
 element.classList.add('y');
-shouldBeEqualToString('element.className', ' y');
+shouldBeEqualToString('element.className', 'y');
 
 
 debug('Test invalid tokens');
 
 // Testing exception due to invalid token
 
 // shouldThrow from js-test.js is not sufficient.
 function shouldThrowDOMException(f, ec)
 {
     try {
@@ skipping 226 matching lines @@
 element.classList.remove('a', 'c');
 shouldBe('observer.takeRecords().length', '1');
 
 // iterable<DOMString>;
 createElement('a b c');
 var seen = [];
 for (var t of element.classList) {
     seen.push(t);
 }
 shouldBeTrue("areArraysEqual(seen, ['a', 'b', 'c'])");