Statsd: Add watchdog rollback to experiment ids

Stores experiment ids to disk for watchdog rollback initiate/success
events as discussed.

Test: gts in topic
Bug: 131768455
Change-Id: I32768fe5c5c21c43811e25d8f87faae0c8d82c1f
diff --git a/cmds/statsd/src/StatsService.h b/cmds/statsd/src/StatsService.h
index a4e6d7f..8d8514f 100644
--- a/cmds/statsd/src/StatsService.h
+++ b/cmds/statsd/src/StatsService.h
@@ -196,6 +196,14 @@
             const std::vector<int64_t>& experimentIdsIn) override;
 
     /**
+     * Binder call to log WatchdogRollbackOccurred atom.
+     */
+    virtual Status sendWatchdogRollbackOccurredAtom(
+            const int32_t rollbackTypeIn,
+            const android::String16& packageNameIn,
+            const int64_t packageVersionCodeIn) override;
+
+    /**
      * Binder call to get registered experiment IDs.
      */
     virtual Status getRegisteredExperimentIds(std::vector<int64_t>* expIdsOut);