Adding support for the MouseWheel event in Streams.

tools/dom/scripts/systemhtml.py

 #!/usr/bin/python
 # 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.
 
 """This module provides shared functionality for the system to generate
 Dart:html APIs from the IDL database."""
 
 import emitter
 import os
@@ skipping 421 matching lines @@
     merged_interface = self._interface_type_info.merged_interface()
     if merged_interface:
       self._backend.AddMembers(self._database.GetInterface(merged_interface),
         not self._backend.ImplementsMergedMembers())
 
     self._backend.AddMembers(self._interface)
     self._backend.AddSecondaryMembers(self._interface)
     self._event_generator.EmitStreamGetters(
         self._interface,
         self._interface.doc_js_name,
-        self._backend.CustomJSMembers(),
+        [],
         self._implementation_members_emitter)
     self._backend.FinishInterface()
 
   def _ImplementationEmitter(self):
     basename = self._interface_type_info.implementation_name()
     if (self._interface_type_info.merged_into() and
         self._backend.ImplementsMergedMembers()):
       # Merged members are implemented in target interface implementation.
       return emitter.Emitter()
     return self._library_emitter.FileEmitter(basename, self._library_name)
@@ skipping 600 matching lines @@
     for library_name in libraries:
       self._libraries[library_name] = DartLibrary(
           library_name, template_loader, library_type, output_dir)
 
   def AddFile(self, basename, library_name, path):
     self._libraries[library_name].AddFile(path)
 
   def Emit(self, emitter, auxiliary_dir):
     for lib in self._libraries.values():
       lib.Emit(emitter, auxiliary_dir)