update_engine: Switch to chrome-dbus for client requests in update_engine

update_engine daemon acts as DBus client to send DBus calls to shill,
power_manager and chrome, and to listen for signals from shill, chrome
and login_manager. This patch migrates these calls and signals to use
chrome-dbus framework instead of dbus-glib.

All references to dbus-glib code are removed.

BUG=chromium:419827
TEST=Updated unittest. Deployed on a link device and tested interactions with shill and chromium.

Change-Id: I31b389e0d1690cccb115ff3b6539c876ba81bd0e
Reviewed-on: https://chromium-review.googlesource.com/290990
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Alex Deymo <deymo@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
Trybot-Ready: Alex Deymo <deymo@chromium.org>
diff --git a/update_manager/state_factory.cc b/update_manager/state_factory.cc
index 54c0205..acefff4 100644
--- a/update_manager/state_factory.cc
+++ b/update_manager/state_factory.cc
@@ -22,17 +22,19 @@
 
 namespace chromeos_update_manager {
 
-State* DefaultStateFactory(policy::PolicyProvider* policy_provider,
-                           chromeos_update_engine::DBusWrapperInterface* dbus,
-                           chromeos_update_engine::SystemState* system_state) {
+State* DefaultStateFactory(
+    policy::PolicyProvider* policy_provider,
+    chromeos_update_engine::ShillProxy* shill_proxy,
+    org::chromium::SessionManagerInterfaceProxyInterface* session_manager_proxy,
+    chromeos_update_engine::SystemState* system_state) {
   chromeos_update_engine::ClockInterface* const clock = system_state->clock();
   unique_ptr<RealConfigProvider> config_provider(
       new RealConfigProvider(system_state->hardware()));
   unique_ptr<RealDevicePolicyProvider> device_policy_provider(
-      new RealDevicePolicyProvider(dbus, policy_provider));
+      new RealDevicePolicyProvider(session_manager_proxy, policy_provider));
   unique_ptr<RealRandomProvider> random_provider(new RealRandomProvider());
   unique_ptr<RealShillProvider> shill_provider(
-      new RealShillProvider(dbus, clock));
+      new RealShillProvider(shill_proxy, clock));
   unique_ptr<RealSystemProvider> system_provider(
       new RealSystemProvider(system_state->hardware()));
   unique_ptr<RealTimeProvider> time_provider(new RealTimeProvider(clock));