Fix call log clear history error handling.

app/src/main/java/org/thoughtcrime/securesms/calls/log/CallLogRepository.kt

@@ -86,6 +86,10 @@ class CallLogRepository(
   /**
    * Delete all call events / unowned links and enqueue clear history job, and then
    * emit a clear history message.
+   *
+   * This explicitly drops failed call link revocations of call links, and those call links
+   * will remain visible to the user. This is safe because the clear history sync message should
+   * only clear local history and then poll link status from the server.
    */
   fun deleteAllCallLogsOnOrBeforeNow(): Single<Int> {
     return Single.fromCallable {
@@ -97,7 +101,7 @@ class CallLogRepository(
       }
 
       SignalDatabase.callLinks.getAllAdminCallLinksExcept(emptySet())
-    }.flatMap(this::revokeAndCollectResults).map { -1 }.subscribeOn(Schedulers.io())
+    }.flatMap(this::revokeAndCollectResults).map { 0 }.subscribeOn(Schedulers.io())
   }
 
   /**