Restructure type tracking in StyleValues to work better with new numeric types

third_party/WebKit/Source/build/scripts/make_css_property_metadata.py

 #!/usr/bin/env python
 # 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.
 
 import sys
 
 import css_properties
 import json5_generator
 from name_utilities import lower_first
 import template_expander
 
 
 class CSSPropertyMetadataWriter(css_properties.CSSProperties):
     filters = {
         'lower_first': lower_first,
     }
 
     def __init__(self, json5_file_path):
         super(CSSPropertyMetadataWriter, self).__init__(json5_file_path)
-        self._outputs = {'CSSPropertyMetadata.cpp': self.generate_css_property_metadata_cpp}
+        self._outputs = {
+            'CSSPropertyMetadata.cpp':
+            self.generate_css_property_metadata_cpp
+        }
+        for property_value in self._properties.values():
+            property_value['supports_percentage'] = (
+                'Percent' in property_value['typedom_types'])
 
     @template_expander.use_jinja('CSSPropertyMetadata.cpp.tmpl', filters=filters)
     def generate_css_property_metadata_cpp(self):
         return {
             'properties_including_aliases': self._properties_including_aliases,
             'switches': [('is_descriptor', 'IsDescriptor'),
                          ('is_property', 'IsProperty'),
                          ('interpolable', 'IsInterpolableProperty'),
                          ('inherited', 'IsInheritedProperty'),
                          ('supports_percentage', 'PropertySupportsPercentage'),
                         ],
             'first_enum_value': self._first_enum_value,
         }
 
 
 if __name__ == '__main__':
     json5_generator.Maker(CSSPropertyMetadataWriter).main()