shill: Reduce log noise.

- Print a single message rather that two messages for each
  auto-connect attempt.

- Don't override Service::AutoConnect in WiFiService because it
  doesn't seem to do anything different now.

- No need to log WiFiEndpoint::PropertiesChanged at INFO level.

BUG=none
TEST=tested on device, ran unit tests

Change-Id: I575d06986a067d42ec9d7c717e284e83e12e460c
Reviewed-on: https://gerrit.chromium.org/gerrit/26226
Commit-Ready: Darin Petkov <petkov@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/service.cc b/service.cc
index 94e4521..6e53dc2 100644
--- a/service.cc
+++ b/service.cc
@@ -236,8 +236,9 @@
 }
 
 void Service::AutoConnect() {
-  const char *reason;
-  if (this->IsAutoConnectable(&reason)) {
+  const char *reason = NULL;
+  if (IsAutoConnectable(&reason)) {
+    LOG(INFO) << "Auto-connecting to " << friendly_name();
     Error error;
     Connect(&error);
   } else {