update_engine: Use org.chromium.KioskAppService service.

Make update_engine use the org.chromium.KioskAppService
D-Bus service exported by Chrome rather than the old methods
under org.chromium.LibCrosService.

BUG=chromium:703229
TEST=unit tests pass; also hacked up RealSystemProvider to
     call its GetKioskAppRequiredPlatformVersion and
     manually verified that the D-Bus call succeeds

Change-Id: I02d503da1e1aec2319c75e2237c87bfcdcd1f7e5
Reviewed-on: https://chromium-review.googlesource.com/987325
Commit-Ready: Dan Erat <derat@chromium.org>
Tested-by: Dan Erat <derat@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
diff --git a/update_manager/real_system_provider.h b/update_manager/real_system_provider.h
index 80a8615..9d71d0d 100644
--- a/update_manager/real_system_provider.h
+++ b/update_manager/real_system_provider.h
@@ -26,7 +26,7 @@
 
 namespace org {
 namespace chromium {
-class LibCrosServiceInterfaceProxyInterface;
+class KioskAppServiceInterfaceProxyInterface;
 }  // namespace chromium
 }  // namespace org
 
@@ -38,11 +38,12 @@
   RealSystemProvider(
       chromeos_update_engine::HardwareInterface* hardware,
       chromeos_update_engine::BootControlInterface* boot_control,
-      org::chromium::LibCrosServiceInterfaceProxyInterface* libcros_proxy)
+      org::chromium::KioskAppServiceInterfaceProxyInterface* kiosk_app_proxy)
       : hardware_(hardware),
 #if USE_CHROME_KIOSK_APP
         boot_control_(boot_control),
-        libcros_proxy_(libcros_proxy) {}
+        kiosk_app_proxy_(kiosk_app_proxy) {
+  }
 #else
         boot_control_(boot_control) {}
 #endif  // USE_CHROME_KIOSK_APP
@@ -83,7 +84,7 @@
   chromeos_update_engine::HardwareInterface* const hardware_;
   chromeos_update_engine::BootControlInterface* const boot_control_;
 #if USE_CHROME_KIOSK_APP
-  org::chromium::LibCrosServiceInterfaceProxyInterface* const libcros_proxy_;
+  org::chromium::KioskAppServiceInterfaceProxyInterface* const kiosk_app_proxy_;
 #endif  // USE_CHROME_KIOSK_APP
 
   DISALLOW_COPY_AND_ASSIGN(RealSystemProvider);