Adding hidden HTMLElement base class back for Dart2JS

sdk/lib/html/dart2js/html_dart2js.dart

Index: sdk/lib/html/dart2js/html_dart2js.dart
diff --git a/sdk/lib/html/dart2js/html_dart2js.dart b/sdk/lib/html/dart2js/html_dart2js.dart
index a00a4122bcc4f361ca4ef6353fa0e1ed37305ec6..da835af246ab589e3f208fbb29a5e6c5ccf752db 100644
--- a/sdk/lib/html/dart2js/html_dart2js.dart
+++ b/sdk/lib/html/dart2js/html_dart2js.dart
@@ -105,7 +105,7 @@ class AbstractWorker extends EventTarget native "AbstractWorker" {
 
 @DocsEditable
 @DomName('HTMLAnchorElement')
-class AnchorElement extends Element native "HTMLAnchorElement" {
+class AnchorElement extends _HTMLElement native "HTMLAnchorElement" {
 
   @DomName('HTMLAnchorElement.HTMLAnchorElement')
   @DocsEditable
@@ -362,7 +362,7 @@ class ApplicationCache extends EventTarget native "ApplicationCache,DOMApplicati
  * on MDN.
  */
 @DomName('HTMLAreaElement')
-class AreaElement extends Element native "HTMLAreaElement" {
+class AreaElement extends _HTMLElement native "HTMLAreaElement" {
 
   @DomName('HTMLAreaElement.HTMLAreaElement')
   @DocsEditable
@@ -464,7 +464,7 @@ class AutocompleteErrorEvent extends Event native "AutocompleteErrorEvent" {
 
 @DocsEditable
 @DomName('HTMLBRElement')
-class BRElement extends Element native "HTMLBRElement" {
+class BRElement extends _HTMLElement native "HTMLBRElement" {
 
   @DomName('HTMLBRElement.HTMLBRElement')
   @DocsEditable
@@ -492,7 +492,7 @@ class BarProp native "BarProp" {
 
 @DocsEditable
 @DomName('HTMLBaseElement')
-class BaseElement extends Element native "HTMLBaseElement" {
+class BaseElement extends _HTMLElement native "HTMLBaseElement" {
 
   @DomName('HTMLBaseElement.HTMLBaseElement')
   @DocsEditable
@@ -567,7 +567,7 @@ class Blob native "Blob" {
 
 @DocsEditable
 @DomName('HTMLBodyElement')
-class BodyElement extends Element native "HTMLBodyElement" {
+class BodyElement extends _HTMLElement native "HTMLBodyElement" {
 
   @DomName('HTMLBodyElement.blurEvent')
   @DocsEditable
@@ -676,7 +676,7 @@ class BodyElement extends Element native "HTMLBodyElement" {
 
 @DocsEditable
 @DomName('HTMLButtonElement')
-class ButtonElement extends Element native "HTMLButtonElement" {
+class ButtonElement extends _HTMLElement native "HTMLButtonElement" {
 
   @DomName('HTMLButtonElement.HTMLButtonElement')
   @DocsEditable
@@ -785,7 +785,7 @@ class Canvas2DContextAttributes native "Canvas2DContextAttributes" {
 
 
 @DomName('HTMLCanvasElement')
-class CanvasElement extends Element implements CanvasImageSource native "HTMLCanvasElement" {
+class CanvasElement extends _HTMLElement implements CanvasImageSource native "HTMLCanvasElement" {
 
   @DomName('HTMLCanvasElement.HTMLCanvasElement')
   @DocsEditable
@@ -1807,7 +1807,7 @@ class Console {
 @SupportedBrowser(SupportedBrowser.CHROME, '26')
 @Experimental
 // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#content-element
-class ContentElement extends Element native "HTMLContentElement" {
+class ContentElement extends _HTMLElement native "HTMLContentElement" {
 
   @DomName('HTMLContentElement.HTMLContentElement')
   @DocsEditable
@@ -6035,7 +6035,7 @@ class CustomEvent extends Event native "CustomEvent" {
 
 @DocsEditable
 @DomName('HTMLDListElement')
-class DListElement extends Element native "HTMLDListElement" {
+class DListElement extends _HTMLElement native "HTMLDListElement" {
 
   @DomName('HTMLDListElement.HTMLDListElement')
   @DocsEditable
@@ -6052,7 +6052,7 @@ class DListElement extends Element native "HTMLDListElement" {
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @SupportedBrowser(SupportedBrowser.IE, '10')
 @SupportedBrowser(SupportedBrowser.SAFARI)
-class DataListElement extends Element native "HTMLDataListElement" {
+class DataListElement extends _HTMLElement native "HTMLDataListElement" {
 
   @DomName('HTMLDataListElement.HTMLDataListElement')
   @DocsEditable
@@ -6222,7 +6222,7 @@ typedef void DatabaseCallback(database);
 @SupportedBrowser(SupportedBrowser.CHROME)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Experimental
-class DetailsElement extends Element native "HTMLDetailsElement" {
+class DetailsElement extends _HTMLElement native "HTMLDetailsElement" {
 
   @DomName('HTMLDetailsElement.HTMLDetailsElement')
   @DocsEditable
@@ -6358,7 +6358,7 @@ class DeviceRotationRate native "DeviceRotationRate" {
 @DocsEditable
 @DomName('HTMLDialogElement')
 @Unstable
-class DialogElement extends Element native "HTMLDialogElement" {
+class DialogElement extends _HTMLElement native "HTMLDialogElement" {
 
   @DomName('HTMLDialogElement.open')
   @DocsEditable
@@ -6598,7 +6598,7 @@ class DirectoryReader native "DirectoryReader" {
  * * [Inline-level element](http://www.w3.org/TR/CSS2/visuren.html#inline-boxes) from W3C.
  */
 @DomName('HTMLDivElement')
-class DivElement extends Element native "HTMLDivElement" {
+class DivElement extends _HTMLElement native "HTMLDivElement" {
 
   @DomName('HTMLDivElement.HTMLDivElement')
   @DocsEditable
@@ -9560,7 +9560,7 @@ abstract class ElementTraversal {
 @SupportedBrowser(SupportedBrowser.IE)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Unstable
-class EmbedElement extends Element native "HTMLEmbedElement" {
+class EmbedElement extends _HTMLElement native "HTMLEmbedElement" {
 
   @DomName('HTMLEmbedElement.HTMLEmbedElement')
   @DocsEditable
@@ -10228,7 +10228,7 @@ class EventTarget native "EventTarget" {
 @DocsEditable
 @DomName('HTMLFieldSetElement')
 @Unstable
-class FieldSetElement extends Element native "HTMLFieldSetElement" {
+class FieldSetElement extends _HTMLElement native "HTMLFieldSetElement" {
 
   @DomName('HTMLFieldSetElement.HTMLFieldSetElement')
   @DocsEditable
@@ -10987,7 +10987,7 @@ class FormData native "FormData" {
 
 @DocsEditable
 @DomName('HTMLFormElement')
-class FormElement extends Element native "HTMLFormElement" {
+class FormElement extends _HTMLElement native "HTMLFormElement" {
 
   @DomName('HTMLFormElement.autocompleteEvent')
   @DocsEditable
@@ -11258,7 +11258,7 @@ class Geoposition native "Geoposition" {
  * An `<hr>` tag.
  */
 @DomName('HTMLHRElement')
-class HRElement extends Element native "HTMLHRElement" {
+class HRElement extends _HTMLElement native "HTMLHRElement" {
 
   @DomName('HTMLHRElement.HTMLHRElement')
   @DocsEditable
@@ -11311,7 +11311,7 @@ class HashChangeEvent extends Event native "HashChangeEvent" {
 
 @DocsEditable
 @DomName('HTMLHeadElement')
-class HeadElement extends Element native "HTMLHeadElement" {
+class HeadElement extends _HTMLElement native "HTMLHeadElement" {
 
   @DomName('HTMLHeadElement.HTMLHeadElement')
   @DocsEditable
@@ -11324,7 +11324,7 @@ class HeadElement extends Element native "HTMLHeadElement" {
 
 @DocsEditable
 @DomName('HTMLHeadingElement')
-class HeadingElement extends Element native "HTMLHeadingElement" {
+class HeadingElement extends _HTMLElement native "HTMLHeadingElement" {
 
   @DomName('HTMLHeadingElement.HTMLHeadingElement')
   @DocsEditable
@@ -11727,7 +11727,7 @@ class HtmlDocument extends Document native "HTMLDocument" {
 
 @DocsEditable
 @DomName('HTMLHtmlElement')
-class HtmlElement extends Element native "HTMLHtmlElement" {
+class HtmlElement extends _HTMLElement native "HTMLHtmlElement" {
 
   @DomName('HTMLHtmlElement.HTMLHtmlElement')
   @DocsEditable
@@ -12390,7 +12390,7 @@ class HttpRequestUpload extends EventTarget native "XMLHttpRequestUpload,XMLHttp
 
 @DocsEditable
 @DomName('HTMLIFrameElement')
-class IFrameElement extends Element native "HTMLIFrameElement" {
+class IFrameElement extends _HTMLElement native "HTMLIFrameElement" {
 
   @DomName('HTMLIFrameElement.HTMLIFrameElement')
   @DocsEditable
@@ -12460,7 +12460,7 @@ class ImageData native "ImageData" {
 
 
 @DomName('HTMLImageElement')
-class ImageElement extends Element implements CanvasImageSource native "HTMLImageElement" {
+class ImageElement extends _HTMLElement implements CanvasImageSource native "HTMLImageElement" {
 
   @DomName('HTMLImageElement.HTMLImageElement')
   @DocsEditable
@@ -12539,7 +12539,7 @@ class ImageElement extends Element implements CanvasImageSource native "HTMLImag
 
 
 @DomName('HTMLInputElement')
-class InputElement extends Element implements
+class InputElement extends _HTMLElement implements
     HiddenInputElement,
     SearchInputElement,
     TextInputElement,
@@ -13598,7 +13598,7 @@ class KeyboardEvent extends UIEvent native "KeyboardEvent" {
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Experimental
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-button-element.html#the-keygen-element
-class KeygenElement extends Element native "HTMLKeygenElement" {
+class KeygenElement extends _HTMLElement native "HTMLKeygenElement" {
 
   @DomName('HTMLKeygenElement.HTMLKeygenElement')
   @DocsEditable
@@ -13669,7 +13669,7 @@ class KeygenElement extends Element native "HTMLKeygenElement" {
 
 @DocsEditable
 @DomName('HTMLLIElement')
-class LIElement extends Element native "HTMLLIElement" {
+class LIElement extends _HTMLElement native "HTMLLIElement" {
 
   @DomName('HTMLLIElement.HTMLLIElement')
   @DocsEditable
@@ -13692,7 +13692,7 @@ class LIElement extends Element native "HTMLLIElement" {
 
 @DocsEditable
 @DomName('HTMLLabelElement')
-class LabelElement extends Element native "HTMLLabelElement" {
+class LabelElement extends _HTMLElement native "HTMLLabelElement" {
 
   @DomName('HTMLLabelElement.HTMLLabelElement')
   @DocsEditable
@@ -13717,7 +13717,7 @@ class LabelElement extends Element native "HTMLLabelElement" {
 
 @DocsEditable
 @DomName('HTMLLegendElement')
-class LegendElement extends Element native "HTMLLegendElement" {
+class LegendElement extends _HTMLElement native "HTMLLegendElement" {
 
   @DomName('HTMLLegendElement.HTMLLegendElement')
   @DocsEditable
@@ -13734,7 +13734,7 @@ class LegendElement extends Element native "HTMLLegendElement" {
 
 @DocsEditable
 @DomName('HTMLLinkElement')
-class LinkElement extends Element native "HTMLLinkElement" {
+class LinkElement extends _HTMLElement native "HTMLLinkElement" {
 
   @DomName('HTMLLinkElement.HTMLLinkElement')
   @DocsEditable
@@ -13868,7 +13868,7 @@ typedef void MidiErrorCallback(DomError error);
 
 @DocsEditable
 @DomName('HTMLMapElement')
-class MapElement extends Element native "HTMLMapElement" {
+class MapElement extends _HTMLElement native "HTMLMapElement" {
 
   @DomName('HTMLMapElement.HTMLMapElement')
   @DocsEditable
@@ -13978,7 +13978,7 @@ class MediaController extends EventTarget native "MediaController" {
 @DocsEditable
 @DomName('HTMLMediaElement')
 @Unstable
-class MediaElement extends Element native "HTMLMediaElement" {
+class MediaElement extends _HTMLElement native "HTMLMediaElement" {
 
   @DomName('HTMLMediaElement.canplayEvent')
   @DocsEditable
@@ -15083,7 +15083,7 @@ class MemoryInfo native "MemoryInfo" {
  *  * [Menu Element](http://www.w3.org/TR/html5/the-menu-element.html#the-menu-element) from the W3C.
  */
 @DomName('HTMLMenuElement')
-class MenuElement extends Element native "HTMLMenuElement" {
+class MenuElement extends _HTMLElement native "HTMLMenuElement" {
 
   @DomName('HTMLMenuElement.HTMLMenuElement')
   @DocsEditable
@@ -15241,7 +15241,7 @@ class MessagePort extends EventTarget native "MessagePort" {
 
 @DocsEditable
 @DomName('HTMLMetaElement')
-class MetaElement extends Element native "HTMLMetaElement" {
+class MetaElement extends _HTMLElement native "HTMLMetaElement" {
 
   @DomName('HTMLMetaElement.content')
   @DocsEditable
@@ -15299,7 +15299,7 @@ typedef void MetadataCallback(Metadata metadata);
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Unstable
-class MeterElement extends Element native "HTMLMeterElement" {
+class MeterElement extends _HTMLElement native "HTMLMeterElement" {
 
   @DomName('HTMLMeterElement.HTMLMeterElement')
   @DocsEditable
@@ -15594,7 +15594,7 @@ class MimeTypeArray extends Interceptor with ListMixin<MimeType>, ImmutableListM
 @DocsEditable
 @DomName('HTMLModElement')
 @Unstable
-class ModElement extends Element native "HTMLModElement" {
+class ModElement extends _HTMLElement native "HTMLModElement" {
 
   @DomName('HTMLModElement.cite')
   @DocsEditable
@@ -17162,7 +17162,7 @@ typedef void _NotificationPermissionCallback(String permission);
 
 @DocsEditable
 @DomName('HTMLOListElement')
-class OListElement extends Element native "HTMLOListElement" {
+class OListElement extends _HTMLElement native "HTMLOListElement" {
 
   @DomName('HTMLOListElement.HTMLOListElement')
   @DocsEditable
@@ -17191,7 +17191,7 @@ class OListElement extends Element native "HTMLOListElement" {
 @SupportedBrowser(SupportedBrowser.IE)
 @SupportedBrowser(SupportedBrowser.SAFARI)
 @Unstable
-class ObjectElement extends Element native "HTMLObjectElement" {
+class ObjectElement extends _HTMLElement native "HTMLObjectElement" {
 
   @DomName('HTMLObjectElement.HTMLObjectElement')
   @DocsEditable
@@ -17271,7 +17271,7 @@ class ObjectElement extends Element native "HTMLObjectElement" {
 
 @DocsEditable
 @DomName('HTMLOptGroupElement')
-class OptGroupElement extends Element native "HTMLOptGroupElement" {
+class OptGroupElement extends _HTMLElement native "HTMLOptGroupElement" {
 
   @DomName('HTMLOptGroupElement.HTMLOptGroupElement')
   @DocsEditable
@@ -17292,7 +17292,7 @@ class OptGroupElement extends Element native "HTMLOptGroupElement" {
 
 @DocsEditable
 @DomName('HTMLOptionElement')
-class OptionElement extends Element native "HTMLOptionElement" {
+class OptionElement extends _HTMLElement native "HTMLOptionElement" {
 
   @DomName('HTMLOptionElement.HTMLOptionElement')
   @DocsEditable
@@ -17355,7 +17355,7 @@ class OptionElement extends Element native "HTMLOptionElement" {
 @SupportedBrowser(SupportedBrowser.CHROME)
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @SupportedBrowser(SupportedBrowser.SAFARI)
-class OutputElement extends Element native "HTMLOutputElement" {
+class OutputElement extends _HTMLElement native "HTMLOutputElement" {
 
   @DomName('HTMLOutputElement.HTMLOutputElement')
   @DocsEditable
@@ -17471,7 +17471,7 @@ class PageTransitionEvent extends Event native "PageTransitionEvent" {
 
 @DocsEditable
 @DomName('HTMLParagraphElement')
-class ParagraphElement extends Element native "HTMLParagraphElement" {
+class ParagraphElement extends _HTMLElement native "HTMLParagraphElement" {
 
   @DomName('HTMLParagraphElement.HTMLParagraphElement')
   @DocsEditable
@@ -17485,7 +17485,7 @@ class ParagraphElement extends Element native "HTMLParagraphElement" {
 @DocsEditable
 @DomName('HTMLParamElement')
 @Unstable
-class ParamElement extends Element native "HTMLParamElement" {
+class ParamElement extends _HTMLElement native "HTMLParamElement" {
 
   @DomName('HTMLParamElement.HTMLParamElement')
   @DocsEditable
@@ -18097,7 +18097,7 @@ typedef void _PositionErrorCallback(PositionError error);
 
 @DocsEditable
 @DomName('HTMLPreElement')
-class PreElement extends Element native "HTMLPreElement" {
+class PreElement extends _HTMLElement native "HTMLPreElement" {
 
   @DomName('HTMLPreElement.HTMLPreElement')
   @DocsEditable
@@ -18143,7 +18143,7 @@ class ProcessingInstruction extends Node native "ProcessingInstruction" {
 @SupportedBrowser(SupportedBrowser.FIREFOX)
 @SupportedBrowser(SupportedBrowser.IE, '10')
 @SupportedBrowser(SupportedBrowser.SAFARI)
-class ProgressElement extends Element native "HTMLProgressElement" {
+class ProgressElement extends _HTMLElement native "HTMLProgressElement" {
 
   @DomName('HTMLProgressElement.HTMLProgressElement')
   @DocsEditable
@@ -18199,7 +18199,7 @@ class ProgressEvent extends Event native "ProgressEvent" {
 
 @DocsEditable
 @DomName('HTMLQuoteElement')
-class QuoteElement extends Element native "HTMLQuoteElement" {
+class QuoteElement extends _HTMLElement native "HTMLQuoteElement" {
 
   @DomName('HTMLQuoteElement.cite')
   @DocsEditable
@@ -19150,7 +19150,7 @@ class Screen native "Screen" {
 
 @DocsEditable
 @DomName('HTMLScriptElement')
-class ScriptElement extends Element native "HTMLScriptElement" {
+class ScriptElement extends _HTMLElement native "HTMLScriptElement" {
 
   @DomName('HTMLScriptElement.HTMLScriptElement')
   @DocsEditable
@@ -19328,7 +19328,7 @@ class SecurityPolicyViolationEvent extends Event native "SecurityPolicyViolation
 
 
 @DomName('HTMLSelectElement')
-class SelectElement extends Element native "HTMLSelectElement" {
+class SelectElement extends _HTMLElement native "HTMLSelectElement" {
 
   @DomName('HTMLSelectElement.HTMLSelectElement')
   @DocsEditable
@@ -19570,7 +19570,7 @@ class Selection native "Selection" {
 @SupportedBrowser(SupportedBrowser.CHROME, '26')
 @Experimental
 // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/shadow/index.html#shadow-element
-class ShadowElement extends Element native "HTMLShadowElement" {
+class ShadowElement extends _HTMLElement native "HTMLShadowElement" {
 
   /// Checks if this type is supported on the current platform.
   static bool get supported => Element.isTagSupported('shadow');
@@ -19761,7 +19761,7 @@ class SourceBufferList extends EventTarget with ListMixin<SourceBuffer>, Immutab
 
 @DocsEditable
 @DomName('HTMLSourceElement')
-class SourceElement extends Element native "HTMLSourceElement" {
+class SourceElement extends _HTMLElement native "HTMLSourceElement" {
 
   @DomName('HTMLSourceElement.HTMLSourceElement')
   @DocsEditable
@@ -19786,7 +19786,7 @@ class SourceElement extends Element native "HTMLSourceElement" {
 
 @DocsEditable
 @DomName('HTMLSpanElement')
-class SpanElement extends Element native "HTMLSpanElement" {
+class SpanElement extends _HTMLElement native "HTMLSpanElement" {
 
   @DomName('HTMLSpanElement.HTMLSpanElement')
   @DocsEditable
@@ -20686,7 +20686,7 @@ typedef void _StringCallback(String data);
 
 @DocsEditable
 @DomName('HTMLStyleElement')
-class StyleElement extends Element native "HTMLStyleElement" {
+class StyleElement extends _HTMLElement native "HTMLStyleElement" {
 
   @DomName('HTMLStyleElement.HTMLStyleElement')
   @DocsEditable
@@ -20775,7 +20775,7 @@ class StyleSheet native "StyleSheet" {
 
 @DocsEditable
 @DomName('HTMLTableCaptionElement')
-class TableCaptionElement extends Element native "HTMLTableCaptionElement" {
+class TableCaptionElement extends _HTMLElement native "HTMLTableCaptionElement" {
 
   @DomName('HTMLTableCaptionElement.HTMLTableCaptionElement')
   @DocsEditable
@@ -20788,7 +20788,7 @@ class TableCaptionElement extends Element native "HTMLTableCaptionElement" {
 
 @DocsEditable
 @DomName('HTMLTableCellElement')
-class TableCellElement extends Element native "HTMLTableCellElement" {
+class TableCellElement extends _HTMLElement native "HTMLTableCellElement" {
 
   @DomName('HTMLTableCellElement.HTMLTableCellElement')
   @DocsEditable
@@ -20817,7 +20817,7 @@ class TableCellElement extends Element native "HTMLTableCellElement" {
 
 @DocsEditable
 @DomName('HTMLTableColElement')
-class TableColElement extends Element native "HTMLTableColElement" {
+class TableColElement extends _HTMLElement native "HTMLTableColElement" {
 
   @DomName('HTMLTableColElement.HTMLTableColElement')
   @DocsEditable
@@ -20834,7 +20834,7 @@ class TableColElement extends Element native "HTMLTableColElement" {
 
 @DocsEditable
 @DomName('HTMLTableElement')
-class TableElement extends Element native "HTMLTableElement" {
+class TableElement extends _HTMLElement native "HTMLTableElement" {
 
   @DomName('HTMLTableElement.tBodies')
   List<TableSectionElement> get tBodies =>
@@ -20942,7 +20942,7 @@ class TableElement extends Element native "HTMLTableElement" {
 
 @DocsEditable
 @DomName('HTMLTableRowElement')
-class TableRowElement extends Element native "HTMLTableRowElement" {
+class TableRowElement extends _HTMLElement native "HTMLTableRowElement" {
 
   @DomName('HTMLTableRowElement.cells')
   List<TableCellElement> get cells =>
@@ -20988,7 +20988,7 @@ class TableRowElement extends Element native "HTMLTableRowElement" {
 
 @DocsEditable
 @DomName('HTMLTableSectionElement')
-class TableSectionElement extends Element native "HTMLTableSectionElement" {
+class TableSectionElement extends _HTMLElement native "HTMLTableSectionElement" {
 
   @DomName('HTMLTableSectionElement.rows')
   List<TableRowElement> get rows =>
@@ -21027,7 +21027,7 @@ class TableSectionElement extends Element native "HTMLTableSectionElement" {
 @SupportedBrowser(SupportedBrowser.CHROME)
 @Experimental
 // https://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/templates/index.html#template-element
-class TemplateElement extends Element native "HTMLTemplateElement" {
+class TemplateElement extends _HTMLElement native "HTMLTemplateElement" {
 
   @DomName('HTMLTemplateElement.HTMLTemplateElement')
   @DocsEditable
@@ -21234,7 +21234,7 @@ class Text extends CharacterData native "Text" {
 
 @DocsEditable
 @DomName('HTMLTextAreaElement')
-class TextAreaElement extends Element native "HTMLTextAreaElement" {
+class TextAreaElement extends _HTMLElement native "HTMLTextAreaElement" {
 
   @DomName('HTMLTextAreaElement.HTMLTextAreaElement')
   @DocsEditable
@@ -21766,7 +21766,7 @@ typedef void TimeoutHandler();
 
 @DocsEditable
 @DomName('HTMLTitleElement')
-class TitleElement extends Element native "HTMLTitleElement" {
+class TitleElement extends _HTMLElement native "HTMLTitleElement" {
 
   @DomName('HTMLTitleElement.HTMLTitleElement')
   @DocsEditable
@@ -22026,7 +22026,7 @@ class TouchList extends Interceptor with ListMixin<Touch>, ImmutableListMixin<To
 @SupportedBrowser(SupportedBrowser.SAFARI)
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-video-element.html#the-track-element
 @Experimental
-class TrackElement extends Element native "HTMLTrackElement" {
+class TrackElement extends _HTMLElement native "HTMLTrackElement" {
 
   @DomName('HTMLTrackElement.HTMLTrackElement')
   @DocsEditable
@@ -22293,7 +22293,7 @@ class UIEvent extends Event native "UIEvent" {
 
 @DocsEditable
 @DomName('HTMLUListElement')
-class UListElement extends Element native "HTMLUListElement" {
+class UListElement extends _HTMLElement native "HTMLUListElement" {
 
   @DomName('HTMLUListElement.HTMLUListElement')
   @DocsEditable
@@ -22306,7 +22306,7 @@ class UListElement extends Element native "HTMLUListElement" {
 
 @DocsEditable
 @DomName('HTMLUnknownElement')
-class UnknownElement extends Element native "HTMLUnknownElement" {
+class UnknownElement extends _HTMLElement native "HTMLUnknownElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25046,7 +25046,7 @@ class _GamepadList extends Interceptor with ListMixin<Gamepad>, ImmutableListMix
 @DomName('HTMLAppletElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#the-applet-element
 @deprecated // deprecated
-abstract class _HTMLAppletElement extends Element native "HTMLAppletElement" {
+abstract class _HTMLAppletElement extends _HTMLElement native "HTMLAppletElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25057,7 +25057,7 @@ abstract class _HTMLAppletElement extends Element native "HTMLAppletElement" {
 @DomName('HTMLBaseFontElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#basefont
 @deprecated // deprecated
-abstract class _HTMLBaseFontElement extends Element native "HTMLBaseFontElement" {
+abstract class _HTMLBaseFontElement extends _HTMLElement native "HTMLBaseFontElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25068,7 +25068,7 @@ abstract class _HTMLBaseFontElement extends Element native "HTMLBaseFontElement"
 @DomName('HTMLDirectoryElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#dir
 @deprecated // deprecated
-abstract class _HTMLDirectoryElement extends Element native "HTMLDirectoryElement" {
+abstract class _HTMLDirectoryElement extends _HTMLElement native "HTMLDirectoryElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25079,7 +25079,7 @@ abstract class _HTMLDirectoryElement extends Element native "HTMLDirectoryElemen
 @DomName('HTMLFontElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#htmlfontelement
 @deprecated // deprecated
-abstract class _HTMLFontElement extends Element native "HTMLFontElement" {
+abstract class _HTMLFontElement extends _HTMLElement native "HTMLFontElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25090,7 +25090,7 @@ abstract class _HTMLFontElement extends Element native "HTMLFontElement" {
 @DomName('HTMLFrameElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#htmlframeelement
 @deprecated // deprecated
-abstract class _HTMLFrameElement extends Element native "HTMLFrameElement" {
+abstract class _HTMLFrameElement extends _HTMLElement native "HTMLFrameElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25101,7 +25101,7 @@ abstract class _HTMLFrameElement extends Element native "HTMLFrameElement" {
 @DomName('HTMLFrameSetElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#frameset
 @deprecated // deprecated
-abstract class _HTMLFrameSetElement extends Element native "HTMLFrameSetElement" {
+abstract class _HTMLFrameSetElement extends _HTMLElement native "HTMLFrameSetElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ -25112,7 +25112,7 @@ abstract class _HTMLFrameSetElement extends Element native "HTMLFrameSetElement"
 @DomName('HTMLMarqueeElement')
 // http://www.whatwg.org/specs/web-apps/current-work/multipage/obsolete.html#the-marquee-element
 @deprecated // deprecated
-abstract class _HTMLMarqueeElement extends Element native "HTMLMarqueeElement" {
+abstract class _HTMLMarqueeElement extends _HTMLElement native "HTMLMarqueeElement" {
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a