Implement {Available|Connected|Enabled}Technolgies and DefaultTechnology

This is Part 1 of a series of changes required for the Manager to generate
the right set of DBus events allowing shill to properly tell Chrome about
connectivity.

Some other side-effects in the change (needed to implement the above):
- Emit these manager properties over DBus everytime we re-sort the Service
  vector.
- Add a technology data member to Device, this allows easy enumeration of
  technologies.
- Add interface for getting a handle to the selected service on a device.
- Map connected state to online instead of ready state. This is needed for
  so that Chrome doesn't wait for the portal detection code to switch the
  state from ready->online.
- Default set the ethernet service as connectable.

BUG=chromium-os:14887
TEST=1) manual test to verify shill properly configures the ethernet
     device and Chrome correctly detects that.
     2) new unit tests

Change-Id: Ib10f2f0836f8d4aacaad1491f58ed9b3b5d37e7d
Reviewed-on: https://gerrit.chromium.org/gerrit/12019
Tested-by: Gaurav Shah <gauravsh@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
diff --git a/manager_dbus_adaptor.cc b/manager_dbus_adaptor.cc
index 27bba64..0bf611c 100644
--- a/manager_dbus_adaptor.cc
+++ b/manager_dbus_adaptor.cc
@@ -57,6 +57,11 @@
   PropertyChanged(name, DBusAdaptor::StringToVariant(value));
 }
 
+void ManagerDBusAdaptor::EmitStringsChanged(const string &name,
+                                            const vector<string> &value) {
+  PropertyChanged(name, DBusAdaptor::StringsToVariant(value));
+}
+
 void ManagerDBusAdaptor::EmitRpcIdentifierArrayChanged(
     const string &name,
     const vector<string> &value) {