Refactor: Inject StatisticsProvider as a dependency of DeviceCloudPolicyInitializer.

chromeos/system/statistics_provider.h

 // Copyright 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.
 
 #ifndef CHROMEOS_SYSTEM_STATISTICS_PROVIDER_H_
 #define CHROMEOS_SYSTEM_STATISTICS_PROVIDER_H_
 
 #include <string>
 
 #include "base/memory/ref_counted.h"
@@ skipping 23 matching lines @@
 // Firmware type and associated values. The values are from crossystem output
 // for the mainfw_type key. Normal and developer correspond to Chrome OS
 // firmware with MP and developer keys respectively, nonchrome indicates the
 // machine doesn't run on Chrome OS firmware. See crossystem source for more
 // details.
 CHROMEOS_EXPORT extern const char kFirmwareTypeKey[];
 CHROMEOS_EXPORT extern const char kFirmwareTypeValueDeveloper[];
 CHROMEOS_EXPORT extern const char kFirmwareTypeValueNonchrome[];
 CHROMEOS_EXPORT extern const char kFirmwareTypeValueNormal[];
 
+// Serial number key (only VPD v2+ devices).  Use GetMachineID() to cover legacy
+// devices.
+CHROMEOS_EXPORT extern const char kSerialNumberKey[];
+
 // HWID key.
 CHROMEOS_EXPORT extern const char kHardwareClassKey[];
 
 // Key/values reporting if Chrome OS is running in a VM or not. These values are
 // read from crossystem output. See crossystem source for VM detection logic.
 CHROMEOS_EXPORT extern const char kIsVmKey[];
 CHROMEOS_EXPORT extern const char kIsVmValueTrue[];
 CHROMEOS_EXPORT extern const char kIsVmValueFalse[];
 
 // OEM customization flag that permits exiting enterprise enrollment flow in
@@ skipping 42 matching lines @@
   // Returns true if the named machine statistic (e.g. "hardware_class") is
   // found and stores it in |result| (if provided). Probing for the existance of
   // a statistic by setting |result| to nullptr supresses the usual warning in
   // case the statistic is not found. Safe to call from any thread except the
   // task runner passed to Initialize() (e.g. FILE). This may block if called
   // early before the statistics are loaded from disk.
   // StartLoadingMachineStatistics() must be called before this.
   virtual bool GetMachineStatistic(const std::string& name,
                                    std::string* result) = 0;
 
-  // Checks whether a machine statistic is present (without logging a warning).
-  bool HasMachineStatistic(const std::string& name);
-
   // Similar to GetMachineStatistic for boolean flags.
   virtual bool GetMachineFlag(const std::string& name, bool* result) = 0;
 
+  // Returns the machine serial number after examining a set of well-known
+  // keys. In case no serial is found, an empty string is returned.
+  std::string GetMachineID();
+
   // Cancels any pending file operations.
   virtual void Shutdown() = 0;
 
   // Returns true if the machine is a VM.
   virtual bool IsRunningOnVm() = 0;
 
   // Get the Singleton instance.
   static StatisticsProvider* GetInstance();
 
   // Set the instance returned by GetInstance() for testing.
   static void SetTestProvider(StatisticsProvider* test_provider);
 
  protected:
   virtual ~StatisticsProvider() {}
 };
 
 }  // namespace system
 }  // namespace chromeos
 
 #endif  // CHROMEOS_SYSTEM_STATISTICS_PROVIDER_H_