Validation of required properties is not working properly

[niho]

Problem

It seems like properties that is listed in the required list, but is not present in the properties will be ignored by the validation. This makes the validated data not properly valid in accordance with the JSON Schema standard, and will fail validation with other validators.

How to reproduce

Example of a schema that reproduces the problem:

{
  "$schema": "http://json-schema.org/schema#",
  "required": [
    "title",
    "description"
  ],
  "properties": {
    "title": {
      "type": "string"
    }
  }
}

The above schema requires both a title and a description property to be present (while the schema for the description property is unspecified). But the json-schema-form validator will simply ignore the description property.