[OriginTrials] Allow origin trials to be installed without an instance object.

third_party/WebKit/Source/bindings/scripts/v8_interface.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 # coding=utf-8
 #
 # 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
@@ skipping 18 matching lines @@
 
 # pylint: disable=relative-import
 
 """Generate template values for an interface.
 
 Design doc: http://www.chromium.org/developers/design-documents/idl-compiler
 """
 
 from collections import defaultdict
 import itertools
-from operator import itemgetter
+from operator import itemgetter, or_
 
 from idl_definitions import IdlOperation, IdlArgument
 from idl_types import IdlType, inherits_interface
 import v8_attributes
 from v8_globals import includes
 import v8_methods
 import v8_types
 import v8_utilities
 from v8_utilities import (cpp_name_or_partial, cpp_name, has_extended_attribute_value,
                           runtime_enabled_function_name, is_legacy_interface_type_checking)
@@ skipping 41 matching lines @@
             constant['origin_trial_feature_name']]
 
 
 def constant_filters():
     return {'has_constant_configuration': filter_has_constant_configuration,
             'has_special_getter': filter_has_special_getter,
             'runtime_enabled_constants': filter_runtime_enabled,
             'origin_trial_enabled_constants': filter_origin_trial_enabled}
 
 
-def origin_trial_feature_names(interface, constants, attributes, methods):
-    """ Returns a list of the names of each origin trial feature used in this interface.
+def origin_trial_features(interface, constants, attributes, methods):
+    """ Returns a list of the origin trial features used in this interface.
 
-    This list is the union of the sets of names used for constants, attributes and methods.
+    Each element is a dictionary with keys 'name' and 'needs_instance'.
+    'needs_instance' is true if any member associated with the interface needs
+    to be installed on every instance of the interface. This list is the union
+    of the sets of features used for constants, attributes and methods.
     """
 
-    feature_names = set(
-        [constant['origin_trial_feature_name'] for constant in constants if constant['origin_trial_feature_name']] +
-        [attribute['origin_trial_feature_name'] for attribute in attributes if attribute['origin_trial_feature_name']] +
-        [method['origin_trial_feature_name'] for method in methods if (
+    # Collect all members visible on this interface with a defined origin trial
+    origin_trial_members = (
+        [constant for constant in constants if constant['origin_trial_feature_name']] +
+        [attribute for attribute in attributes if attribute['origin_trial_feature_name']] +
+        [method for method in methods if (
             v8_methods.method_is_visible(method, interface.is_partial) and
             method['origin_trial_feature_name'])]
     )
-    if feature_names:
+    # Group members by origin_trial_feature_name
+    members_by_name = itertools.groupby(origin_trial_members, itemgetter('origin_trial_feature_name'))

[Marijn Kruisselbrink, 2016/07/08 19:44:09]

itertools.groupby requires the passed in iterable to be sorted already by the
key you're grouping on. You don't seem to actually sort origin_trial_members,
thus this can result in duplicates ending up in members_by_name (and thus also
in features later on).

+    # Construct the list of dictionaries. 'needs_instance' will be true if any
+    # member for the feature has 'on_instance' defined as true.
+    features = [{'name': name,
+                 'needs_instance': reduce(or_, (member.get('on_instance', False)
+                                                for member in members))}
+                for name, members in members_by_name]
+    if features:
         includes.add('bindings/core/v8/ScriptState.h')
         includes.add('core/origin_trials/OriginTrials.h')
-    return sorted(feature_names)
+    return sorted(features)
 
 
 def interface_context(interface):
     includes.clear()
     includes.update(INTERFACE_CPP_INCLUDES)
     header_includes = set(INTERFACE_H_INCLUDES)
 
     if interface.is_partial:
         # A partial interface definition cannot specify that the interface
         # inherits from another interface. Inheritance must be specified on
@@ skipping 435 matching lines @@
         'named_property_getter': property_getter(interface.named_property_getter, ['propertyName']),
         'named_property_setter': property_setter(interface.named_property_setter, interface),
         'named_property_deleter': property_deleter(interface.named_property_deleter),
     })
     context.update({
         'has_named_properties_object': is_global and context['named_property_getter'],
     })
 
     # Origin Trials
     context.update({
-        'origin_trial_feature_names': origin_trial_feature_names(interface, context['constants'], context['attributes'], context['methods']),
+        'origin_trial_features': origin_trial_features(interface, context['constants'], context['attributes'], context['methods']),
     })
     return context
 
 
 # [DeprecateAs], [OriginTrialEnabled], [Reflect], [RuntimeEnabled]
 def constant_context(constant, interface):
     extended_attributes = constant.extended_attributes
 
     return {
         'cpp_class': extended_attributes.get('PartialInterfaceImplementedAs'),
@@ skipping 788 matching lines @@
     extended_attributes = deleter.extended_attributes
     is_call_with_script_state = v8_utilities.has_extended_attribute_value(deleter, 'CallWith', 'ScriptState')
     is_ce_reactions = 'CEReactions' in extended_attributes
     return {
         'is_call_with_script_state': is_call_with_script_state,
         'is_ce_reactions': is_ce_reactions,
         'is_custom': 'Custom' in extended_attributes,
         'is_raises_exception': 'RaisesException' in extended_attributes,
         'name': cpp_name(deleter),
     }