Load the agent into surefire forks

[dustinbyrne]

The following configuration will not load the agent:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>${maven-surefire-plugin.version}</version>
    <configuration>
        <forkCount>0</forkCount>
        <reuseForks>true</reuseForks>
        <argLine>
            --illegal-access=permit
        </argLine>
    </configuration>
</plugin>

[ptrdvrk]

Two issues:

1. forking must be enabled for a new JVM with the -javaagent parameter to be forked
2. argLine requires a reference of the argLine prepared by upstream plugins

The following configuration works:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>${maven-surefire-plugin.version}</version>
    <configuration>
        <forkCount>1</forkCount>
        <reuseForks>true</reuseForks>
        <argLine>
            @{argLine} --illegal-access=permit
        </argLine>
    </configuration>
</plugin>

[ptrdvrk]

@dustinbyrne shall we close this one? Forking is required for the agent to work as you cannot attach it to an existing running JVM (where the tests are run if forkCount==1).