RFR 8200118: [test] String concat tests should test toString() application order

[Paul Sandoz]

> On Mar 22, 2018, at 2:46 PM, Aleksey Shipilev <shade at redhat.com> wrote:
> 
> On 03/22/2018 10:37 PM, Paul Sandoz wrote:
>> Test looks good, but do you need to declare the source/target for compilation?
> 
> Thanks! source/target are from the times when default source/target was not 9, all other tests have
> it (I copypasted the test from the existing ones). We should probably ditch those source/target-s
> all at once soon.
> 

Ok,
Paul.