Don't generate FooList if it behaves like List<Foo> exactly.

lib/html/scripts/systemhtml.py

Index: lib/html/scripts/systemhtml.py
===================================================================
--- lib/html/scripts/systemhtml.py	(revision 12656)
+++ lib/html/scripts/systemhtml.py	(working copy)
@@ -217,8 +217,6 @@
   'writestart': 'writeStart'
 }
 
-
-
 # Information for generating element constructors.
 #
 # TODO(sra): maybe remove all the argument complexity and use cascades.
@@ -460,9 +458,13 @@
     self._backend.GenerateLibraries(self._dart_file_paths)
 
   def _CreateEmitter(self, filename):
-    path = os.path.join(self._output_dir, 'dart', filename)
-    self._dart_file_paths.append(path)
-    return self._emitters.FileEmitter(path)
+    is_native_class = filename[:-len('.dart')] in nativified_classes.values()

[vsm, 2012/09/21 22:43:12]

This feels brittle.  If we change the file naming convention, a bunch of types
will
mysteriously appear.  Can you fix this upstream to not emit if the type name is
nativified?

[Emily Fortuna, 2012/09/22 00:13:52]

Unfortunately not. The backend _Impl files are very tightly coupled with the
front end interfaces. It constructs the backend implementations by using the
members added to the front end interface. So you have to actually allow the
construction of the front-facing interface to complete in order for the backends
to also build.

+    if is_native_class:
+      return emitter.Emitter()
+    else:
+      path = os.path.join(self._output_dir, 'dart', filename)
+      self._dart_file_paths.append(path)
+      return self._emitters.FileEmitter(path)
 
 # ------------------------------------------------------------------------------
 
@@ -562,7 +564,10 @@
 
     if self._backend.HasImplementation():
       if not self._interface.id in _merged_html_interfaces:
-        filename = '%sImpl.dart' % self._html_interface_name
+        name = self._html_interface_name
+        if self._html_interface_name in nativified_classes:
+          name = nativified_classes[self._html_interface_name]
+        filename = '%sImpl.dart' % name
       else:
         filename = '%sImpl_Merged.dart' % self._html_interface_name
       self._implementation_emitter = self._system._CreateEmitter(filename)
@@ -782,7 +787,10 @@
     return True
 
   def _ImplClassName(self, type_name):
-    return '_%sImpl' % type_name
+    name = type_name
+    if type_name in nativified_classes:
+      name = nativified_classes[type_name]
+    return '_%sImpl' % name
 
   def StartInterface(self):
     interface = self._interface