Update AppCompacted WW atom to include device ZRAM usage.

We log free ZRAM in kilobytes before and after the compaction event.

Test: manually verified am_compact and statsd logging looks correct.
Bug: 123623746

Change-Id: I20d5991fb1d060584d415b76c30769fe9f049ffd
diff --git a/cmds/statsd/src/atoms.proto b/cmds/statsd/src/atoms.proto
index 7ddb783..1c7eb41 100644
--- a/cmds/statsd/src/atoms.proto
+++ b/cmds/statsd/src/atoms.proto
@@ -4746,6 +4746,12 @@
 
   // The process state at the time of compaction.
   optional android.app.ProcessStateEnum process_state = 16 [default = PROCESS_STATE_UNKNOWN];
+
+  // Free ZRAM in kilobytes before compaction.
+  optional int64 before_zram_free_kilobytes = 17;
+
+  // Free ZRAM in kilobytes after compaction.
+  optional int64 after_zram_free_kilobytes = 18;
 }
 
 /**