shill: improve log message in vpn_service

When we skip a connect request because the service is already
connected, or connecting, log the fact that either is a possibility.

BUG=None
TEST=unit tests

Change-Id: I82ad783482d5b2bf02812860c44fe9830f06ce00
Reviewed-on: https://gerrit.chromium.org/gerrit/57487
Commit-Queue: mukesh agrawal <quiche@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
diff --git a/vpn_service.cc b/vpn_service.cc
index 0e8771d..fcf3aa0 100644
--- a/vpn_service.cc
+++ b/vpn_service.cc
@@ -43,9 +43,16 @@
 VPNService::~VPNService() {}
 
 void VPNService::Connect(Error *error, const char *reason) {
-  if (IsConnected() || IsConnecting()) {
-    Error::PopulateAndLog(
-        error, Error::kAlreadyConnected, "VPN service already connected.");
+  if (IsConnected()) {
+    Error::PopulateAndLog(error, Error::kAlreadyConnected,
+                          StringPrintf("VPN service %s already connected.",
+                                       unique_name().c_str()));
+    return;
+  }
+  if (IsConnecting()) {
+    Error::PopulateAndLog(error, Error::kInProgress,
+                          StringPrintf("VPN service %s already connecting.",
+                                       unique_name().c_str()));
     return;
   }
   Service::Connect(error, reason);
diff --git a/vpn_service_unittest.cc b/vpn_service_unittest.cc
index 17e91fb..0517d51 100644
--- a/vpn_service_unittest.cc
+++ b/vpn_service_unittest.cc
@@ -125,7 +125,7 @@
   error.Reset();
   SetServiceState(Service::kStateConfiguring);
   service_->Connect(&error, "in test");
-  EXPECT_EQ(Error::kAlreadyConnected, error.type());
+  EXPECT_EQ(Error::kInProgress, error.type());
 }
 
 TEST_F(VPNServiceTest, Disconnect) {