Convert keys in dataSet to camelCase instead of dasherized.

tests/html/htmlelement_test.dart

 library ElementTest;
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_config.dart';
 import 'dart:html';
 
 main() {
   useHtmlConfiguration();
   test('InnerHTML', () {
     Element element = new Element.tag('div');
     element.id = 'test';
@@ skipping 69 matching lines @@
     expect(div.dataset.length, 2);
     expect(div.dataset.isEmpty, isFalse);
 
     expect(div.dataset.remove('foo'), 'foo-value');
     expect(div.dataset.length, 1);
     expect(div.dataset.isEmpty, isFalse);
 
     div.dataset.clear();
     expect(div.dataset.length, 0);
     expect(div.dataset.isEmpty, isTrue);
+
+    Element otherDiv = new Element.html(
+        '<div id="dataDiv" data-my-message="Hello World"></div>',
+        treeSanitizer: new UnhelpfulSanitizer());
+    expect(otherDiv.dataset.containsKey('myMessage'), isTrue);
+
+    Element anotherDiv = new Element.html(
+        '<div id="dataDiv" data-eggs="bacon"></div>',
+        treeSanitizer: new UnhelpfulSanitizer());
+    expect(anotherDiv.dataset.containsKey('eggs'), isTrue);
   });
 }
+
+/**
+ * A sanitizer that doesn't actually do anything! Allows us to add custom
+ * attributes (and anything else).
+ */
+class UnhelpfulSanitizer implements NodeTreeSanitizer {

[blois, 2013/10/10 21:13:39]

import utils.dart and use NullTreeSanitizer from there.

+  UnhelpfulSanitizer();
+  void sanitizeTree(Node node) {}
+}