Provide table of wrapper types for dart:blink

tools/dom/templates/html/dartium/html_dartium.darttemplate

Index: tools/dom/templates/html/dartium/html_dartium.darttemplate
diff --git a/tools/dom/templates/html/dartium/html_dartium.darttemplate b/tools/dom/templates/html/dartium/html_dartium.darttemplate
index 279a3ece997f67101d19656c6321b9ddc7d947ee..96610b14863c312b86b1dbbfd5e0e40e5e23875d 100644
--- a/tools/dom/templates/html/dartium/html_dartium.darttemplate
+++ b/tools/dom/templates/html/dartium/html_dartium.darttemplate
@@ -139,3 +139,23 @@ Future<Isolate> spawnDomUri(Uri uri, List<String> args, message) {
   // TODO(17738): Plumb arguments and return value through.
   return _Utils.spawnDomUri(uri.toString());
 }
+$if DART_USE_BLINK
+// FIXME: This should be generated.
+const _typeMap = const {
+  'EventTarget': EventTarget,
+  'Window': Window,
+  'Element': Element,
+  'Console': Console,
+  'Node': Node,
+  'Document': Document,
+  'HTMLElement': HtmlElement,
+  'HTMLCanvasElement': CanvasElement,
+  'HTMLDocument': HtmlDocument,
+};
+
+Type _getType(String key) {
+  if (!_typeMap.containsKey(key))
+    return null;
+  return _typeMap[key];
+}
+$endif