Reapply Futureification.

tools/dom/scripts/htmldartgenerator.py

Index: tools/dom/scripts/htmldartgenerator.py
diff --git a/tools/dom/scripts/htmldartgenerator.py b/tools/dom/scripts/htmldartgenerator.py
index 2b2b0847e918c1880e5cd4f81e7ba974b88248db..2f13d48413ebdeb932b5feeb23da072e6ce06d18 100644
--- a/tools/dom/scripts/htmldartgenerator.py
+++ b/tools/dom/scripts/htmldartgenerator.py
@@ -10,7 +10,8 @@ import emitter
 from generator import AnalyzeOperation, ConstantOutputOrder, \
     DartDomNameOfAttribute, FindMatchingAttribute, IsDartCollectionType, \
     IsPureInterface, TypeOrNothing, GetAnnotationsAndComments, \
-    FormatAnnotationsAndComments
+    FormatAnnotationsAndComments, ConvertToFuture, GetCallbackInfo
+from htmlrenamer import convert_to_future_members
 
 # Types that are accessible cross-frame in a limited fashion.
 # In these cases, the base type (e.g., WindowBase) provides restricted access
@@ -89,6 +90,9 @@ class HtmlDartGenerator(object):
       operations = operationsById[id]
       info = AnalyzeOperation(interface, operations)
       self.AddOperation(info, declare_only)
+      if ('%s.%s' % (interface.id, info.declared_name) in
+          convert_to_future_members):
+        self.AddOperation(ConvertToFuture(info), declare_only)
 
   def AddSecondaryMembers(self, interface):
     # With multiple inheritance, attributes and operations of non-first
@@ -454,6 +458,50 @@ class HtmlDartGenerator(object):
           GenerateCall,
           IsOptional)
 
+  def _AddFutureifiedOperation(self, info, html_name):
+    """Given a API function that uses callbacks, convert it to using Futures.
+
+    This conversion assumes the success callback is always provided before the
+    error callback (and so far in the DOM API, this is the case)."""
+    callback_info = GetCallbackInfo(
+        self._database.GetInterface(info.callback_args[0].type_id))
+
+    param_list = info.ParametersAsArgumentList()
+    annotations = ''
+    if '_RenamingAnnotation' in dir(self):
+      annotations = (self._RenamingAnnotation(info.declared_name, html_name) +
+          self._Annotations(info.type_name, info.declared_name))
+    self._members_emitter.Emit(
+        '\n'
+        '  $ANNOTATIONS$MODIFIERS$TYPE$FUTURE_GENERIC $NAME($PARAMS) {\n'
+        '    var completer = new Completer$(FUTURE_GENERIC)();\n'
+        '    $ORIGINAL_FUNCTION($PARAMS_LIST\n'
+        '        $NAMED_PARAM($VARIABLE_NAME) { '
+        'completer.complete($VARIABLE_NAME); }'
+        '$ERROR_CALLBACK);\n'
+        '    return completer.future;\n'
+        '  }\n',
+        ANNOTATIONS=annotations,
+        MODIFIERS='static ' if info.IsStatic() else '',
+        TYPE=self.SecureOutputType(info.type_name),
+        NAME=html_name[1:],
+        PARAMS=info.ParametersDeclaration(self._NarrowInputType
+            if '_NarrowInputType' in dir(self) else self._DartType),
+        PARAMS_LIST='' if param_list == '' else param_list + ',',
+        NAMED_PARAM=('%s : ' % info.callback_args[0].name
+            if info.requires_named_arguments and
+              info.callback_args[0].is_optional else ''),
+        VARIABLE_NAME= '' if len(callback_info.param_infos) == 0 else 'value',
+        ERROR_CALLBACK=('' if len(info.callback_args) == 1 else
+            (',\n        %s(error) { completer.completeError(error); }' %
+            ('%s : ' % info.callback_args[1].name
+            if info.requires_named_arguments and
+                info.callback_args[1].is_optional else ''))),
+        FUTURE_GENERIC = ('' if len(callback_info.param_infos) == 0 or
+            not callback_info.param_infos[0].type_id else
+            '<%s>' % self._DartType(callback_info.param_infos[0].type_id)),
+        ORIGINAL_FUNCTION = html_name)
+
   def EmitHelpers(self, base_class):
     pass