Add regular expression support in json_schema component

components/json_schema/json_schema_validator.h

 // Copyright 2013 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.
 
 #ifndef COMPONENTS_JSON_SCHEMA_JSON_SCHEMA_VALIDATOR_H_
 #define COMPONENTS_JSON_SCHEMA_JSON_SCHEMA_VALIDATOR_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 14 matching lines @@
 //
 // There is also an older JavaScript implementation of the same functionality in
 // chrome/renderer/resources/json_schema.js.
 //
 // The following features of JSON Schema are not implemented:
 // - requires
 // - unique
 // - disallow
 // - union types (but replaced with 'choices')
 // - number.maxDecimal
-// - string.pattern
 //
 // The following properties are not applicable to the interface exposed by
 // this class:
 // - options
 // - readonly
 // - title
 // - description
 // - format
 // - default
 // - transient
 // - hidden
 //
 // There are also these departures from the JSON Schema proposal:
 // - null counts as 'unspecified' for optional values
 // - added the 'choices' property, to allow specifying a list of possible types
 //   for a value
 // - by default an "object" typed schema does not allow additional properties.
 //   if present, "additionalProperties" is to be a schema against which all
 //   additional properties will be validated.
+// - regular expression supports all syntaxes that re2 accepts.
+//   See https://code.google.com/p/re2/wiki/Syntax for details.
 //==============================================================================
 class JSONSchemaValidator {
  public:
   // Details about a validation error.
   struct Error {
     Error();
 
     explicit Error(const std::string& message);
 
     Error(const std::string& path, const std::string& message);
@@ skipping 174 matching lines @@
   bool default_allow_additional_properties_;
 
   // Errors accumulated since the last call to Validate().
   std::vector<Error> errors_;
 
 
   DISALLOW_COPY_AND_ASSIGN(JSONSchemaValidator);
 };
 
 #endif  // COMPONENTS_JSON_SCHEMA_JSON_SCHEMA_VALIDATOR_H_