We no longer assign ids to unregistered threads. We don't have any stack
trace for thread creation for these worker threads, so this shouldn't
affect report quality much.
llvm-svn: 277514
// CHECK: AddressSanitizer: stack-buffer-underflow on address [[ADDR:0x[0-9a-f]+]]
// CHECK: WRITE of size 1 at [[ADDR]] thread T1
// CHECK: {{#0 .* work_item.*queue_user_work_item_report.cc}}:[[@LINE-3]]
-// CHECK: Address [[ADDR]] is located in stack of thread T1 at offset {{.*}} in frame
-// CHECK: work_item
SetEvent(done);
return 0;
}