RFR: 8245455: Remove alternative StringConcatFactory strategies

[Aleksey Shipilev]

On 5/22/20 11:52 AM, Claes Redestad wrote:
> Webrev: http://cr.openjdk.java.net/~redestad/8245455/open.00/

The experience with dealing with string concat bugs tells me we better leave at least one strategy
as the fallback. It does not have to be very optimized, but it needs to be definitely correct. BC_SB
seems to fit the bill here.

-- 
Thanks,
-Aleksey