Add |device_heartbeat_settings| to device policy proto

chrome/browser/chromeos/policy/proto/chrome_device_policy.proto

 // 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.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package enterprise_management;
 
@@ skipping 576 matching lines @@
 message RebootOnShutdownProto {
   // Determines whether the device automatically reboots whenever the user shuts
   // it down. If this flag is set to true, shutdown is forbidden and UI elements
   // trigger a device reboot instead of a power off. This policy affects
   // shutdowns triggered from the UI only. If the user shuts down the device
   // using the power button, it will not automatically reboot, even if the
   // policy is enabled.
   optional bool reboot_on_shutdown = 1 [default = false];
 }
 
+// Settings that control whether a device would send heartbeat messages to GCM,
+// and how frequently to send these.
+message DeviceHeartbeatSettingsProto {
+  // Whether the device should send heartbeat messages. The default is false.
+  optional bool heartbeat_enabled = 1 [default = false];
+
+  // How frequently devices send heartbeats back to server. The unit is in
+  // milliseconds. The default is 2 minutes.
+  optional int64 heartbeat_frequency = 2 [default = 120000];
+}
+
 message ChromeDeviceSettingsProto {
   optional DevicePolicyRefreshRateProto device_policy_refresh_rate = 1;
   optional UserWhitelistProto user_whitelist = 2;
   optional GuestModeEnabledProto guest_mode_enabled = 3;
   optional DeviceProxySettingsProto device_proxy_settings = 4;
   optional CameraEnabledProto camera_enabled = 5;
   optional ShowUserNamesOnSigninProto show_user_names = 6;
   optional DataRoamingEnabledProto data_roaming_enabled = 7;
   optional AllowNewUsersProto allow_new_users = 8;
   optional MetricsEnabledProto metrics_enabled = 9;
@@ skipping 17 matching lines @@
   optional VariationsParameterProto variations_parameter = 25;
   optional AttestationSettingsProto attestation_settings = 26;
   optional AccessibilitySettingsProto accessibility_settings = 27;
   optional SupervisedUsersSettingsProto supervised_users_settings = 28;
   optional LoginScreenPowerManagementProto login_screen_power_management = 29;
   optional SystemUse24HourClockProto use_24hour_clock = 30;
   optional AutoCleanupSettigsProto auto_clean_up_settings = 31;
   optional SystemSettingsProto system_settings = 32;
   optional SAMLSettingsProto saml_settings = 33;
   optional RebootOnShutdownProto reboot_on_shutdown = 34;
+  optional DeviceHeartbeatSettingsProto device_heartbeat_settings = 35;
 }