RFR 8237858: PlainSocketImpl.socketAccept() handles EINTR incorrectly

[Alan Bateman]

Vyom,

Are you planning to create a native test for this? I realize the fix you 
are discussing here isn't too interesting for >= JDK 13 but I think it 
could be useful to ensure that we have a test that signals threads in 
all of the blocking operations (connect might be tricky butt at least 
read, write, and accept).

-Alan