[shill] Enable the getting of properties, and wire to dbus.

PropertyStore exposes getters for iterators pointing to the beginning
and end of its property maps, and a static utility method in DBusAdaptor
uses these to iterate through all the properties in the PropertyStore and build
up a map of property name -> DBus::Variant-wrapped value.

BUG=chromium-os:16343
TEST=unit tests

Change-Id: I85ebbaee167ab2feed0fcf8fe654274de352aca0
Reviewed-on: http://gerrit.chromium.org/gerrit/3359
Reviewed-by: Chris Masone <cmasone@chromium.org>
Tested-by: Chris Masone <cmasone@chromium.org>
diff --git a/property_store_unittest.cc b/property_store_unittest.cc
index aa22e0d..03b6ee1 100644
--- a/property_store_unittest.cc
+++ b/property_store_unittest.cc
@@ -40,13 +40,13 @@
     DBusAdaptor::StringToVariant("");
 // static
 const ::DBus::Variant PropertyStoreTest::kStringmapV =
-    DBusAdaptor::StringmapToVariant(map<string, string>());
+    DBusAdaptor::StringmapToVariant(Stringmap());
 // static
 const ::DBus::Variant PropertyStoreTest::kStringmapsV =
     DBusAdaptor::StringmapsToVariant(vector<map<string, string> >());
 // static
 const ::DBus::Variant PropertyStoreTest::kStringsV =
-    DBusAdaptor::StringsToVariant(vector<string>(1, ""));
+    DBusAdaptor::StringsToVariant(Strings(1, ""));
 // static
 const ::DBus::Variant PropertyStoreTest::kUint16V =
     DBusAdaptor::Uint16ToVariant(0);