shill: don't auto-connect to a disconnected service

This addresses part of the problem with the 003AsciiKeyWEP40
failure. That test establishes a connection, disconnects,
reconfigures the (WEP) password on an AP, and then tries
to reconnect.

Before this patch, the test failed as follows:
1. shill immediately tries to reconnect after the disconnect.
   This reconnect uses the old password (because the test
   hasn't had a chance to supply a new password).
2. The test code provides the correct password, and then
   initiates an explicit connect. However, the explicit
   connect is ignored, because a connection is already in
   progress (to the same service).
3. The automatic reconnect fails, because it is using the
   wrong password.

BUG=chromium-os:25153,chromium-os:25157
TEST=unit tests, WiFiRoaming, WiFiSecMat.*WEP*, WiFiManager

Testing notes:
- WiFiRoaming had some failures, but no regressions
- WiFiSecMat.*WEP* passed except 003CheckWEP_8021x
  (previously, that failed in addition to 000StaticKeyWEP40,
  001StaticKeyWEP104, 005SharedKeyWEP40, and 006SharedKeyWEP104.)
- WiFiManager passed
  (previously, 003AsciiKeyWEP40 and 004AsciiKeyWEP104 failed.)

Change-Id: I2dd6312006865c914d4193ce3f7d7c5443b84deb
Reviewed-on: https://gerrit.chromium.org/gerrit/14408
Commit-Ready: mukesh agrawal <quiche@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
diff --git a/service_unittest.cc b/service_unittest.cc
index eb0c9b6..51f9d12 100644
--- a/service_unittest.cc
+++ b/service_unittest.cc
@@ -281,6 +281,28 @@
   service_->set_connectable(true);
   EXPECT_TRUE(service_->IsAutoConnectable());
 
+  // We should not auto-connect to a Service that a user has
+  // deliberately disconnected.
+  Error error;
+  service_->Disconnect(&error);
+  EXPECT_FALSE(service_->IsAutoConnectable());
+
+  // But if the Service is reloaded, it is eligible for auto-connect
+  // again.
+  NiceMock<MockStore> storage;
+  EXPECT_CALL(storage, ContainsGroup(storage_id_)).WillOnce(Return(true));
+  EXPECT_TRUE(service_->Load(&storage));
+  EXPECT_TRUE(service_->IsAutoConnectable());
+
+  // A deliberate Connect should also re-enable auto-connect.
+  service_->Disconnect(&error);
+  EXPECT_FALSE(service_->IsAutoConnectable());
+  service_->Connect(&error);
+  EXPECT_TRUE(service_->IsAutoConnectable());
+
+  // TODO(quiche): After we have resume handling in place, test that
+  // we re-enable auto-connect on resume. crosbug.com/25213
+
   service_->SetState(Service::kStateConnected);
   EXPECT_FALSE(service_->IsAutoConnectable());