First cut of mini dart:html.

tool/input_sdk/lib/html/html_common/metadata.dart

+// 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
+// BSD-style license that can be found in the LICENSE file.
+
+library metadata;
+
+/**
+ * An annotation used to mark a feature as only being supported by a subset
+ * of the browsers that Dart supports by default.
+ *
+ * If an API is not annotated with [SupportedBrowser] then it is assumed to
+ * work on all browsers Dart supports.
+ */
+class SupportedBrowser {
+  static const String CHROME = "Chrome";
+  static const String FIREFOX = "Firefox";
+  static const String IE = "Internet Explorer";
+  static const String OPERA = "Opera";
+  static const String SAFARI = "Safari";
+
+  /// The name of the browser.
+  final String browserName;
+  /// The minimum version of the browser that supports the feature, or null
+  /// if supported on all versions.
+  final String minimumVersion;
+
+  const SupportedBrowser(this.browserName, [this.minimumVersion]);
+}
+
+
+/**
+ * An annotation used to mark an API as being experimental.
+ *
+ * An API is considered to be experimental if it is still going through the
+ * process of stabilizing and is subject to change or removal.
+ *
+ * See also:
+ *
+ * * [W3C recommendation](http://en.wikipedia.org/wiki/W3C_recommendation)
+ */
+class Experimental {
+  const Experimental();
+}
+
+
+/**
+ * Annotation that specifies that a member is editable through generate files.
+ *
+ * This is used for API generation.
+ *
+ * [name] should be formatted as `interface.member`.
+ */
+class DomName {
+  final String name;
+  const DomName(this.name);
+}
+
+
+/**
+ * Metadata that specifies that that member is editable through generated
+ * files.
+ */
+class DocsEditable {
+  const DocsEditable();
+}
+
+
+/**
+ * Annotation that indicates that an API is not expected to change but has
+ * not undergone enough testing to be considered stable.
+ */
+class Unstable {
+  const Unstable();
+}