bindings: Supports inheritance of [Unforgeable] attributes as accessor-type properties.

Source/bindings/scripts/utilities.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Utility functions (file reading, simple IDL parsing by regexes) for IDL build.
 
 Design doc: http://www.chromium.org/developers/design-documents/idl-build
 """
 
 import os
@@ skipping 164 matching lines @@
     @property
     def include_path_for_export(self):
         return 'modules/ModulesExport.h'
 
 
 def load_interfaces_info_overall_pickle(info_dir):
     with open(os.path.join(info_dir, 'modules', 'InterfacesInfoOverall.pickle')) as interface_info_file:
         return pickle.load(interface_info_file)
 
 
+def merge_dict_recursively(target, diff):
+    """Merges two dicts into one.
+    |target| will be updated with |diff|.  Part of |diff| may be re-used in
+    |target|.
+    """
+    for key, value in diff.iteritems():
+        if key not in target:
+            target[key] = value
+        elif type(value) == dict:
+            merge_dict_recursively(target[key], value)
+        elif type(value) == list:
+            target[key].extend(value)
+        elif type(value) == set:
+            target[key].update(value)
+        else:
+            # Testing IDLs want to overwrite the values.  Production code
+            # doesn't need any overwriting.
+            target[key] = value
+
+
 def create_component_info_provider_core(info_dir):
     interfaces_info = load_interfaces_info_overall_pickle(info_dir)
     with open(os.path.join(info_dir, 'core', 'ComponentInfoCore.pickle')) as component_info_file:
         component_info = pickle.load(component_info_file)
     return ComponentInfoProviderCore(interfaces_info, component_info)
 
 
 def create_component_info_provider_modules(info_dir):
     interfaces_info = load_interfaces_info_overall_pickle(info_dir)
     with open(os.path.join(info_dir, 'core', 'ComponentInfoCore.pickle')) as component_info_file:
@@ skipping 153 matching lines @@
     extended_attributes_string = match.group(1)
     match = re.search(r'[^=]\bExposed\(([^)]*)\)', file_contents)
     if not match:
         return None
     arguments = []
     for argument in map(string.strip, match.group(1).split(',')):
         exposed, runtime_enabled = argument.split()
         arguments.append({'exposed': exposed, 'runtime_enabled': runtime_enabled})
 
     return arguments