Remove ProxyResolver from update_engine

Current ProxyResolver code only supports no-proxy. Therefore it is
barely any use. Remove current implementation for a better one.

Test: th
Bug: 235816007
Change-Id: Ieb46dedf6c6ea86b11c81d7691c2adb578d3d97d
diff --git a/aosp/update_attempter_android.h b/aosp/update_attempter_android.h
index 5d832e0..f3feed0 100644
--- a/aosp/update_attempter_android.h
+++ b/aosp/update_attempter_android.h
@@ -31,15 +31,13 @@
 #include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/common/action_processor.h"
 #include "update_engine/common/boot_control_interface.h"
-#include "update_engine/common/clock.h"
+#include "update_engine/common/clock_interface.h"
 #include "update_engine/common/daemon_state_interface.h"
 #include "update_engine/common/download_action.h"
 #include "update_engine/common/hardware_interface.h"
 #include "update_engine/common/metrics_reporter_interface.h"
 #include "update_engine/common/network_selector_interface.h"
 #include "update_engine/common/prefs_interface.h"
-#include "update_engine/common/service_observer_interface.h"
-#include "update_engine/metrics_utils.h"
 #include "update_engine/payload_consumer/filesystem_verifier_action.h"
 #include "update_engine/payload_consumer/postinstall_runner_action.h"
 
@@ -248,9 +246,6 @@
   // set back in the middle of an update.
   base::TimeTicks last_notify_time_;
 
-  // Only direct proxy supported.
-  DirectProxyResolver proxy_resolver_;
-
   // The processor for running Actions.
   std::unique_ptr<ActionProcessor> processor_;