Make it easier to use JSON libraries other than Jackson alongside REST Docs

Reproduce the failure with the Gradle spring-restdocs-mockmvc:1.1.0.RELEASE dependency and the dispatcher-servlet.xml configuration shown in the issue. Start at the mvc:message-converters setup and inspect why GsonHttpMessageConverter is absent when REST Docs is added. Done means the existing custom converters remain available and the tests no longer crash.

My spring project works fine,
but tests crashes when I add spring-restdocs to gradle dependencies.
Just that (no configuration chages, no test code changes) brakes my project.

The problem is that spring-restdocs library make spring framework ignore mvc:message-converters configuration. (I'm not sure what is exactly happened)
I added gson over jackson for JSON as you can see below.
but with spring-restdocs, only I see is messageConverters without GsonHttpMessageConverter.

I have configuration like this: dispatcher-servlet.xml (there are applicationContext.xml and applicationContext-rest.xml as well)

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd">

<!-- message converter -->
    <mvc:annotation-driven content-negotiation-manager="contentNegotiationManager">
        <mvc:message-converters>
            <ref bean="jaxbMessageConverter" />
            <ref bean="gsonMessageConverter" />
        </mvc:message-converters>
    </mvc:annotation-driven>

    <bean id="gsonMessageConverter" class="org.springframework.http.converter.json.GsonHttpMessageConverter"/>
    <bean id="jaxbMessageConverter" class="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">
        <property name="marshaller" ref="jaxbMarshaller" />
        <property name="unmarshaller" ref="jaxbUnmarshaller" />
        <property name="supportedMediaTypes">
            <list>
                <value>application/xml</value>
                <value>application/xml;charset=UTF-8</value>
            </list>
        </property>
    </bean>

    <bean id="jaxbMarshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller">
        <property name="packagesToScan">
            <list>
                <value>foo.boo.**.output</value>
            </list>
        </property>
    </bean>
    <bean id="jaxbUnmarshaller" name="unmarshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller">
        <property name="packagesToScan">
            <list>
                <value>foo.boo.**.model</value>
            </list>
        </property>
    </bean>
</beans>

gradle

dependencies {
    testCompile 'org.springframework.restdocs:spring-restdocs-mockmvc:1.1.0.RELEASE'
}