Introduce [Exposed(Arguments)] in IDL code generator.

Source/bindings/scripts/idl_definitions.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 632 matching lines @@
 class IdlImplement(object):
     def __init__(self, node):
         self.left_interface = node.GetName()
         self.right_interface = node.GetProperty('REFERENCE')
 
 
 ################################################################################
 # Extended attributes
 ################################################################################
 
+class Exposure:
+    """An Exposure holds one Exposed or RuntimeEnabled condition.
+    Each exposure has two properties: exposed and runtime_enabled.
+    Exposure(e, r) corresponds to [Exposed(e r)]. Exposure(e) corresponds to
+    [Exposed=e].
+    """
+    def __init__(self, exposed, runtime_enabled=None):
+        self.exposed = exposed
+        self.runtime_enabled = runtime_enabled
+
+
 def ext_attributes_node_to_extended_attributes(idl_name, node):
     """
     Returns:
       Dictionary of {ExtAttributeName: ExtAttributeValue}.
       Value is usually a string, with these exceptions:
       Constructors: value is a list of Arguments nodes, corresponding to
         possible signatures of the constructor.
       CustomConstructors: value is a list of Arguments nodes, corresponding to
         possible signatures of the custom constructor.
       NamedConstructor: value is a Call node, corresponding to the single
@@ skipping 36 matching lines @@
         elif name == 'NamedConstructor':
             if child_class and child_class != 'Call':
                 raise ValueError('[NamedConstructor] only supports Call as child, but has child of class: %s' % child_class)
             extended_attributes[name] = child
         elif name == 'SetWrapperReferenceTo':
             if not child:
                 raise ValueError('[SetWrapperReferenceTo] requires a child, but has none.')
             if child_class != 'Arguments':
                 raise ValueError('[SetWrapperReferenceTo] only supports Arguments as child, but has child of class: %s' % child_class)
             extended_attributes[name] = arguments_node_to_arguments(idl_name, child)
+        elif name == 'Exposed':
+            if child_class and child_class != 'Arguments':
+                raise ValueError('[Exposed] only supports Arguments as child, but has child of class: %s' % child_class)
+            exposures = []
+            if child_class == 'Arguments':
+                exposures = [Exposure(exposed=str(arg.idl_type),
+                                      runtime_enabled=arg.name)
+                             for arg in arguments_node_to_arguments('*', child)]
+            else:
+                value = extended_attribute_node.GetProperty('VALUE')
+                if type(value) is str:
+                    exposures = [Exposure(exposed=value)]
+                else:
+                    exposures = [Exposure(exposed=v) for v in value]
+            extended_attributes[name] = exposures
         elif child:
             raise ValueError('ExtAttributes node with unexpected children: %s' % name)
         else:
             value = extended_attribute_node.GetProperty('VALUE')
             extended_attributes[name] = value
 
     # Store constructors and custom constructors in special list attributes,
     # which are deleted later. Note plural in key.
     if constructors:
         extended_attributes['Constructors'] = constructors
@@ skipping 115 matching lines @@
     child_class = child.GetClass()
     if child_class != 'Type':
         raise ValueError('Unrecognized node class: %s' % child_class)
     return type_node_to_type(child)
 
 
 def union_type_node_to_idl_union_type(node):
     member_types = [type_node_to_type(member_type_node)
                     for member_type_node in node.GetChildren()]
     return IdlUnionType(member_types)