Add network throttling as an enterprise policy

chrome/browser/chromeos/BUILD.gn

Index: chrome/browser/chromeos/BUILD.gn
diff --git a/chrome/browser/chromeos/BUILD.gn b/chrome/browser/chromeos/BUILD.gn
index 1b494e37dbf5950579769483308d1d9a6fb988df..c089926a446962726494025d679e23f8eb98b188 100644
--- a/chrome/browser/chromeos/BUILD.gn
+++ b/chrome/browser/chromeos/BUILD.gn
@@ -926,6 +926,8 @@ source_set("chromeos") {
     "net/network_portal_web_dialog.h",
     "net/network_state_notifier.cc",
     "net/network_state_notifier.h",
+    "net/network_throttling_observer.cc",
+    "net/network_throttling_observer.h",
     "net/onc_utils.cc",
     "net/onc_utils.h",
     "net/proxy_config_handler.cc",
@@ -1482,6 +1484,7 @@ source_set("unit_tests") {
     "net/network_portal_detector_impl_unittest.cc",
     "net/network_portal_notification_controller_unittest.cc",
     "net/network_state_notifier_unittest.cc",
+    "net/network_throttling_observer_unittest.cc",
     "net/wake_on_wifi_manager_unittest.cc",
     "options/network_property_ui_data_unittest.cc",
     "ownership/fake_owner_settings_service.cc",