Switch from expecting a reconnection to *not* doing do

If we're aborting mirror operations early, a couple of specs need to
change sense.

tests/acceptance/fakes/dest/hello_wrong_magic.rb

@@ -1,22 +1,24 @@
 #!/usr/bin/env ruby
 
 # Simulate a destination which sends the wrong magic.
-# We expect the sender to disconnect and reconnect.
 
 require 'flexnbd/fake_dest'
 include FlexNBD
+Thread.abort_on_exception
 
 addr, port = *ARGV
 server = FakeDest.new( addr, port )
 client1 = server.accept
 
-# Launch a second thread so that we can spot the reconnection attempt
-# as soon as it happens, or alternatively die a flaming death on
-# timeout.
+# We don't expect a reconnection attempt.
 t = Thread.new do
+  begin
     client2 = server.accept( "Timed out waiting for a reconnection",
                             FlexNBD::MS_RETRY_DELAY_SECS + 1 )
-  client2.close
+    fail "Unexpected reconnection"
+  rescue Timeout::Error
+    #expected
+  end
 end
 
 client1.write_hello( :magic => :wrong )

tests/acceptance/fakes/dest/reject_acl.rb

@@ -1,6 +1,7 @@
 #!/usr/bin/env ruby
 
 # Accept a connection, then immediately close it.  This simulates an ACL rejection.
+# We do not expect a reconnection.
 
 require 'flexnbd/fake_dest'
 include FlexNBD
@@ -9,6 +10,15 @@ addr, port = *ARGV
 server = FakeDest.new( addr, port )
 server.accept.close
 
+
+begin
+  server.accept
+  fail "Unexpected reconnection"
+rescue Timeout::Error
+  # expected
+end
+
 server.close
 
+
 exit(0)