RFR 8210395: Add doc to SecurityTools.java

[Sean Mullan]

Looks fine to me.

--Sean

On 9/24/18 11:59 PM, Weijun Wang wrote:
> Ping again.
> 
>> On Sep 5, 2018, at 12:17 PM, Weijun Wang <weijun.wang at oracle.com> wrote:
>>
>> I ran javadoc on test/lib so I can learn the useful helper classes, and find out SecurityTools.java has no javadoc at all.
>>
>> Please review this change
>>
>>    http://cr.openjdk.java.net/~weijun/8210395/webrev.00/
>>
>> Thanks
>> Max
>>
>