shill: logging improvements

- in sorted service list, include the reason that service A
  comes before service B
- set friendly name for ethernet service
  (so they no longer log as "0")
- log argument to Connection::SetIsDefault

BUG=None
TEST=unit tests

Change-Id: I34f893cad0ba76be988171868540327105e9dd50
Reviewed-on: https://gerrit.chromium.org/gerrit/16401
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
Commit-Ready: mukesh agrawal <quiche@chromium.org>
diff --git a/connection.cc b/connection.cc
index a80271f..43095ec 100644
--- a/connection.cc
+++ b/connection.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -78,7 +78,7 @@
 }
 
 void Connection::SetIsDefault(bool is_default) {
-  VLOG(2) << __func__;
+  VLOG(2) << __func__ << " " << is_default_ << " -> " << is_default;
   if (is_default == is_default_) {
     return;
   }