[sensors](CrOS/Linux) Implement Sensor device manager for sensors

device/BUILD.gn

Index: device/BUILD.gn
diff --git a/device/BUILD.gn b/device/BUILD.gn
index 6ed38c003fbd17212d0ed411ac4e3da69f87cb77..be4b49dafa61bfe380b6214f62c703f6a40fdd4c 100644
--- a/device/BUILD.gn
+++ b/device/BUILD.gn
@@ -63,6 +63,7 @@ test("device_unittests") {
     "bluetooth/test/test_bluetooth_local_gatt_service_delegate.h",
     "gamepad/gamepad_provider_unittest.cc",
     "gamepad/public/interfaces/gamepad_struct_traits_unittest.cc",
+    "generic_sensor/platform_sensor_and_provider_unittest_linux.cc",
     "generic_sensor/platform_sensor_and_provider_unittest_win.cc",
     "generic_sensor/platform_sensor_provider_unittest.cc",
     "power_monitor/power_monitor_message_broadcaster_unittest.cc",
@@ -108,10 +109,6 @@ test("device_unittests") {
     deps += [ "//dbus:test_support" ]
   }
 
-  if (is_linux) {
-    sources += [ "generic_sensor/linux/sensor_reader_unittest.cc" ]
-  }
-
   # HID and Serial:
   # Android doesn't compile.
   # Linux, requires udev.