Compile update_engine without shill.

Add a new BRILLO_USE_SHILL for shill, it depends on BRILLO_USE_DBUS.

Bug: 30746265
Test: mma with USE_SHILL=1 and USE_DBUS=1
Test: mma with USE_SHILL=0 and USE_DBUS=1
Test: mma with USE_SHILL=0 and USE_DBUS=0

Change-Id: Ia5ef7a7c7cf48e81c2dd0e4326eeac0f7c0248b3
diff --git a/update_manager/state_factory.cc b/update_manager/state_factory.cc
index 6c8808b..2b3ce63 100644
--- a/update_manager/state_factory.cc
+++ b/update_manager/state_factory.cc
@@ -25,6 +25,9 @@
 #endif  // USE_DBUS
 
 #include "update_engine/common/clock_interface.h"
+#if USE_DBUS
+#include "update_engine/dbus_connection.h"
+#endif  // USE_DBUS
 #include "update_engine/update_manager/fake_shill_provider.h"
 #include "update_engine/update_manager/real_config_provider.h"
 #include "update_engine/update_manager/real_device_policy_provider.h"
@@ -33,11 +36,10 @@
 #include "update_engine/update_manager/real_system_provider.h"
 #include "update_engine/update_manager/real_time_provider.h"
 #include "update_engine/update_manager/real_updater_provider.h"
-#if USE_DBUS
-#include "update_engine/dbus_connection.h"
+#if USE_SHILL
 #include "update_engine/shill_proxy.h"
 #include "update_engine/update_manager/real_shill_provider.h"
-#endif  // USE_DBUS
+#endif  // USE_SHILL
 
 using std::unique_ptr;
 
@@ -58,13 +60,16 @@
           brillo::make_unique_ptr(
               new org::chromium::SessionManagerInterfaceProxy(bus)),
           policy_provider));
-  unique_ptr<RealShillProvider> shill_provider(
-      new RealShillProvider(new chromeos_update_engine::ShillProxy(), clock));
 #else
   unique_ptr<RealDevicePolicyProvider> device_policy_provider(
       new RealDevicePolicyProvider(policy_provider));
-  unique_ptr<FakeShillProvider> shill_provider(new FakeShillProvider());
 #endif  // USE_DBUS
+#if USE_SHILL
+  unique_ptr<RealShillProvider> shill_provider(
+      new RealShillProvider(new chromeos_update_engine::ShillProxy(), clock));
+#else
+  unique_ptr<FakeShillProvider> shill_provider(new FakeShillProvider());
+#endif  // USE_SHILL
   unique_ptr<RealRandomProvider> random_provider(new RealRandomProvider());
   unique_ptr<RealSystemProvider> system_provider(new RealSystemProvider(
       system_state->hardware(), system_state->boot_control(), libcros_proxy));
@@ -75,9 +80,9 @@
   if (!(config_provider->Init() &&
         device_policy_provider->Init() &&
         random_provider->Init() &&
-#if USE_DBUS
+#if USE_SHILL
         shill_provider->Init() &&
-#endif  // USE_DBUS
+#endif  // USE_SHILL
         system_provider->Init() &&
         time_provider->Init() &&
         updater_provider->Init())) {