Revert of chromeos: Don't send empty power management policies.

chromeos/dbus/power_policy_controller.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chromeos/dbus/power_policy_controller.h"
 
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
@@ skipping 116 matching lines @@
     str += base::StringPrintf("wait_for_initial_user_activity=%d ",
         policy.wait_for_initial_user_activity());
   }
   if (policy.has_reason())
     str += base::StringPrintf("reason=\"%s\" ", policy.reason().c_str());
   TrimWhitespace(str, TRIM_TRAILING, &str);
   return str;
 }
 
 PowerPolicyController::PowerPolicyController()
-    : client_(NULL),
+    : manager_(NULL),
+      client_(NULL),
       prefs_were_set_(false),
       honor_screen_wake_locks_(true),
       next_wake_lock_id_(1) {
 }
 
 PowerPolicyController::~PowerPolicyController() {
-  if (client_) {
-    client_->RemoveObserver(this);
-    client_ = NULL;
-  }
+  DCHECK(manager_);
+  // The power manager's policy is reset before this point, in
+  // OnDBusThreadManagerDestroying().  At the time that
+  // PowerPolicyController is destroyed, PowerManagerClient's D-Bus proxy
+  // to the power manager is already gone.
+  client_->RemoveObserver(this);
+  client_ = NULL;
+  manager_->RemoveObserver(this);
+  manager_ = NULL;
 }
 
 void PowerPolicyController::Init(DBusThreadManager* manager) {
-  client_ = manager->GetPowerManagerClient();
+  manager_ = manager;
+  manager_->AddObserver(this);
+  client_ = manager_->GetPowerManagerClient();
   client_->AddObserver(this);
+  SendCurrentPolicy();
 }
 
 void PowerPolicyController::ApplyPrefs(const PrefValues& values) {
   prefs_policy_.Clear();
 
   power_manager::PowerManagementPolicy::Delays* delays =
       prefs_policy_.mutable_ac_delays();
   delays->set_screen_dim_ms(values.ac_screen_dim_delay_ms);
   delays->set_screen_off_ms(values.ac_screen_off_delay_ms);
   delays->set_screen_lock_ms(values.ac_screen_lock_delay_ms);
@@ skipping 41 matching lines @@
       values.user_activity_screen_dim_delay_factor);
   prefs_policy_.set_wait_for_initial_user_activity(
       values.wait_for_initial_user_activity);
 
   honor_screen_wake_locks_ = values.allow_screen_wake_locks;
 
   prefs_were_set_ = true;
   SendCurrentPolicy();
 }
 
+void PowerPolicyController::ClearPrefs() {
+  prefs_policy_.Clear();
+  honor_screen_wake_locks_ = true;
+  prefs_were_set_ = false;
+  SendCurrentPolicy();
+}
+
 int PowerPolicyController::AddScreenWakeLock(const std::string& reason) {
   int id = next_wake_lock_id_++;
   screen_wake_locks_[id] = reason;
   SendCurrentPolicy();
   return id;
 }
 
 int PowerPolicyController::AddSystemWakeLock(const std::string& reason) {
   int id = next_wake_lock_id_++;
   system_wake_locks_[id] = reason;
   SendCurrentPolicy();
   return id;
 }
 
 void PowerPolicyController::RemoveWakeLock(int id) {
   if (!screen_wake_locks_.erase(id) && !system_wake_locks_.erase(id))
     LOG(WARNING) << "Ignoring request to remove nonexistent wake lock " << id;
   else
     SendCurrentPolicy();
 }
 
+void PowerPolicyController::OnDBusThreadManagerDestroying(
+    DBusThreadManager* manager) {
+  DCHECK_EQ(manager, manager_);
+  SendEmptyPolicy();
+}
+
 void PowerPolicyController::PowerManagerRestarted() {
   SendCurrentPolicy();
 }
 
 void PowerPolicyController::SendCurrentPolicy() {
   std::string reason;
 
   power_manager::PowerManagementPolicy policy = prefs_policy_;
   if (prefs_were_set_)
     reason = "Prefs";
@@ skipping 27 matching lines @@
   for (WakeLockMap::const_iterator it = system_wake_locks_.begin();
        it != system_wake_locks_.end(); ++it) {
     reason += (reason.empty() ? "" : ", ") + it->second;
   }
 
   if (!reason.empty())
     policy.set_reason(reason);
   client_->SetPolicy(policy);
 }
 
+void PowerPolicyController::SendEmptyPolicy() {
+  client_->SetPolicy(power_manager::PowerManagementPolicy());
+}
+
 }  // namespace chromeos