[Chromoting] Use device::PowerSaveBlocker to block screen saver

remoting/host/remoting_me2me_host.cc

Index: remoting/host/remoting_me2me_host.cc
diff --git a/remoting/host/remoting_me2me_host.cc b/remoting/host/remoting_me2me_host.cc
index dd5e5fc8af3822341a54e20f43afcc882367729c..3c1d98630d0be81e278602d82b08d6f92ad848ba 100644
--- a/remoting/host/remoting_me2me_host.cc
+++ b/remoting/host/remoting_me2me_host.cc
@@ -61,6 +61,7 @@
 #include "remoting/host/host_event_logger.h"
 #include "remoting/host/host_exit_codes.h"
 #include "remoting/host/host_main.h"
+#include "remoting/host/host_power_save_blocker.h"
 #include "remoting/host/host_status_logger.h"
 #include "remoting/host/input_injector.h"
 #include "remoting/host/ipc_desktop_environment.h"
@@ -401,6 +402,7 @@ class HostProcess : public ConfigWatcher::Delegate,
       host_change_notification_listener_;
   std::unique_ptr<HostStatusLogger> host_status_logger_;
   std::unique_ptr<HostEventLogger> host_event_logger_;
+  std::unique_ptr<HostPowerSaveBlocker> power_save_blocker_;
 
   std::unique_ptr<ChromotingHost> host_;
 
@@ -1472,6 +1474,11 @@ void HostProcess::StartHost() {
       host_->AsWeakPtr(), ServerLogEntry::ME2ME,
       signal_strategy_.get(), directory_bot_jid_));
 
+  power_save_blocker_.reset(new HostPowerSaveBlocker(
+      host_->AsWeakPtr(),
+      context_->ui_task_runner(),
+      context_->file_task_runner()));
+
   // Set up reporting the host status notifications.
 #if defined(REMOTING_MULTI_PROCESS)
   host_event_logger_.reset(
@@ -1535,6 +1542,7 @@ void HostProcess::GoOffline(const std::string& host_offline_reason) {
   host_.reset();
   host_event_logger_.reset();
   host_status_logger_.reset();
+  power_save_blocker_.reset();
   host_change_notification_listener_.reset();
 
   // Before shutting down HostSignalingManager, send the |host_offline_reason|