Fixing up DOM constructors.

tools/dom/scripts/systemhtml.py

Index: tools/dom/scripts/systemhtml.py
diff --git a/tools/dom/scripts/systemhtml.py b/tools/dom/scripts/systemhtml.py
index 90d2610856e7cd158934610b771c677fd00cee79..04e491d95d330c2a376d4e602fd53464e428aadb 100644
--- a/tools/dom/scripts/systemhtml.py
+++ b/tools/dom/scripts/systemhtml.py
@@ -540,9 +540,14 @@ class HtmlDartInterfaceGenerator(object):
         self._library_name, self._interface, None, '')
 
     class_modifiers = ''
-    if self._renamer.ShouldSuppressInterface(self._interface):
+    if (self._renamer.ShouldSuppressInterface(self._interface) or
+        IsPureInterface(self._interface.id)):
       class_modifiers = 'abstract '
 
+    native_spec = ''
+    if not IsPureInterface(self._interface.id):
+      native_spec = self._backend.NativeSpec()
+
     self._implementation_members_emitter = implementation_emitter.Emit(
         self._backend.ImplementationTemplate(),
         LIBRARYNAME='dart.dom.%s' % self._library_name,
@@ -553,7 +558,7 @@ class HtmlDartInterfaceGenerator(object):
         IMPLEMENTS=implements_str,
         MIXINS=mixins_str,
         DOMNAME=self._interface.doc_js_name,
-        NATIVESPEC=self._backend.NativeSpec())
+        NATIVESPEC=native_spec)
     self._backend.StartInterface(self._implementation_members_emitter)
 
     self._backend.EmitHelpers(base_class)
@@ -632,9 +637,6 @@ class Dart2JSBackend(HtmlDartGenerator):
     return ' native "%s"' % native_spec
 
   def ImplementationTemplate(self):
-    if IsPureInterface(self._interface.id):
-      return self._template_loader.Load('pure_interface.darttemplate')
-
     template_file = ('impl_%s.darttemplate' %
                      self._interface.doc_js_name)
     return (self._template_loader.TryLoad(template_file) or
@@ -897,6 +899,9 @@ class Dart2JSBackend(HtmlDartGenerator):
   def AmendIndexer(self, element_type):
     pass
 
+  def RootClassName(self):
+    return 'Interceptor'
+
   def EmitOperation(self, info, html_name):
     """
     Arguments: