Correct variable name for last update check time

Align the name of the last update check time variable to the units
within it (seconds since epoch).

Bug: 70178109
Test: unit-tests
Change-Id: Ic06890f0e234528d80dc1bcd053e8b602c6f9309
(cherry picked from commit 4adf279cecb8b6c5f85d66e504b9c847b72e0e4c)
diff --git a/parcelable_update_engine_status.cc b/parcelable_update_engine_status.cc
index d3e7eaa..8a2dbeb 100644
--- a/parcelable_update_engine_status.cc
+++ b/parcelable_update_engine_status.cc
@@ -26,7 +26,7 @@
 
 ParcelableUpdateEngineStatus::ParcelableUpdateEngineStatus(
     const UpdateEngineStatus& status)
-    : last_checked_time_(status.last_checked_time_ms),
+    : last_checked_time_(status.last_checked_time),
       current_operation_(
           chromeos_update_engine::UpdateStatusToString(status.status)),
       progress_(status.progress),