Reland "Replace Chrome IPC with Mojo IPC for querying BatteryStatus service"

device/battery/battery_status_manager_chromeos.cc

 // Copyright 2014 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 "content/browser/battery_status/battery_status_manager.h"
+#include "device/battery/battery_status_manager.h"
 
 #include "base/memory/ref_counted.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager/power_supply_properties.pb.h"
 #include "chromeos/dbus/power_manager_client.h"
-#include "content/public/browser/browser_thread.h"
-#include "third_party/WebKit/public/platform/WebBatteryStatus.h"
 
-namespace content {
+namespace device {
 
 namespace {
 
 class PowerManagerObserver
     : public chromeos::PowerManagerClient::Observer,
       public base::RefCountedThreadSafe<PowerManagerObserver> {
  public:
   explicit PowerManagerObserver(
       const BatteryStatusService::BatteryUpdateCallback& callback)
       : callback_(callback), currently_listening_(false) {}
 
-  // Starts listening for updates. It is safe to call this on any thread.
+  // Starts listening for updates.
   void Start() {
-    if (BrowserThread::CurrentlyOn(BrowserThread::UI)) {
-      StartOnUI();
-    } else {
-      BrowserThread::PostTask(
-          BrowserThread::UI,
-          FROM_HERE,
-          base::Bind(&PowerManagerObserver::StartOnUI, this));
-    }
+    if (currently_listening_)
+      return;
+    chromeos::PowerManagerClient* power_client =
+        chromeos::DBusThreadManager::Get()->GetPowerManagerClient();
+    power_client->AddObserver(this);
+    power_client->RequestStatusUpdate();
+    currently_listening_ = true;
   }
 
-  // Stops listening for updates. It is safe to call this on any thread.
+  // Stops listening for updates.
   void Stop() {
-    if (BrowserThread::CurrentlyOn(BrowserThread::UI)) {
-      StopOnUI();
-    } else {
-      BrowserThread::PostTask(
-          BrowserThread::UI,
-          FROM_HERE,
-          base::Bind(&PowerManagerObserver::StopOnUI, this));
-    }
+    if (!currently_listening_)
+      return;
+    chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->RemoveObserver(
+        this);
+    currently_listening_ = false;
   }
 
  private:
   friend class base::RefCountedThreadSafe<PowerManagerObserver>;
 
   virtual ~PowerManagerObserver() {}
 
   bool IsBatteryPresent(
       const power_manager::PowerSupplyProperties& proto) const {
     return proto.battery_state() !=
@@ skipping 16 matching lines @@
     return proto.battery_state() ==
            power_manager::PowerSupplyProperties_BatteryState_FULL;
   }
 
   double GetBatteryLevel(
       const power_manager::PowerSupplyProperties& proto) const {
     const double kMaxBatteryLevelProto = 100.f;
     return proto.battery_percent() / kMaxBatteryLevelProto;
   }
 
-  void StartOnUI() {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-    if (currently_listening_)
-      return;
-    chromeos::PowerManagerClient* power_client =
-        chromeos::DBusThreadManager::Get()->GetPowerManagerClient();
-    power_client->AddObserver(this);
-    power_client->RequestStatusUpdate();
-    currently_listening_ = true;
-  }
-
-  void StopOnUI() {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-    if (!currently_listening_)
-      return;
-    chromeos::DBusThreadManager::Get()->GetPowerManagerClient()->RemoveObserver(
-        this);
-    currently_listening_ = false;
-  }
-
   // chromeos::PowerManagerClient::Observer:
   virtual void PowerChanged(
       const power_manager::PowerSupplyProperties& proto) override {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-    blink::WebBatteryStatus status;
+    BatteryStatus status;
+
     // Use the default values if there is no battery in the system.
     if (IsBatteryPresent(proto)) {
       // The charging status is unreliable if a low power charger is connected
       // (i.e. usb).
       bool status_unreliable = IsUsbChargerConnected(proto);
       // Battery time is unreliable if it is still being computed.
       bool time_unreliable =
           status_unreliable || proto.is_calculating_battery_time();
 
       // Set |charging| only if the status is reliable. Otherwise, keep the
       // default (which is |true|).
       if (!status_unreliable)
         status.charging = IsBatteryCharging(proto);
 
       // Set |chargingTime| to +infinity if the battery is discharging, or if
       // the time is unreliable. Keep the default value (which is 0) if the
       // battery is full.
       if (time_unreliable || !status.charging)
-        status.chargingTime = std::numeric_limits<double>::infinity();
+        status.charging_time = std::numeric_limits<double>::infinity();
       else if (!IsBatteryFull(proto))
-        status.chargingTime = proto.battery_time_to_full_sec();
+        status.charging_time = proto.battery_time_to_full_sec();
 
       // Keep the default value for |dischargingTime| (which is +infinity) if
       // the time is unreliable, or if the battery is charging.
       if (!time_unreliable && !status.charging)
-        status.dischargingTime = proto.battery_time_to_empty_sec();
+        status.discharging_time = proto.battery_time_to_empty_sec();
 
       status.level = GetBatteryLevel(proto);
     }
     callback_.Run(status);
   }
 
   BatteryStatusService::BatteryUpdateCallback callback_;
   bool currently_listening_;
 
   DISALLOW_COPY_AND_ASSIGN(PowerManagerObserver);
 };
 
 class BatteryStatusManagerChromeOS
     : public BatteryStatusManager,
       public chromeos::PowerManagerClient::Observer {
  public:
   explicit BatteryStatusManagerChromeOS(
       const BatteryStatusService::BatteryUpdateCallback& callback)
       : observer_(new PowerManagerObserver(callback)) {}
 
   virtual ~BatteryStatusManagerChromeOS() { observer_->Stop(); }
 
  private:
   // BatteryStatusManager:
   virtual bool StartListeningBatteryChange() override {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
     observer_->Start();
     return true;
   }
 
   virtual void StopListeningBatteryChange() override {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
     observer_->Stop();
   }
 
   scoped_refptr<PowerManagerObserver> observer_;
 
   DISALLOW_COPY_AND_ASSIGN(BatteryStatusManagerChromeOS);
 };
 
 }  // namespace
 
 // static
 scoped_ptr<BatteryStatusManager> BatteryStatusManager::Create(
     const BatteryStatusService::BatteryUpdateCallback& callback) {
   return scoped_ptr<BatteryStatusManager>(
       new BatteryStatusManagerChromeOS(callback));
 }
 
-}  // namespace content
+}  // namespace device