Add support for AttachmentBackfill sync messages.

app/src/main/java/org/thoughtcrime/securesms/jobmanager/Job.java

@@ -42,6 +42,7 @@ public abstract class Job {
   private long lastRunAttemptTime;
   private long nextBackoffInterval;
 
+  private volatile boolean cascadingFailure;
   private volatile boolean canceled;
 
   protected Context context;
@@ -106,6 +107,16 @@ public abstract class Job {
     this.canceled = true;
   }
 
+  /** Indicates that this job is failing because a job earlier in the chain failed. */
+  final void markCascadingFailure() {
+    this.cascadingFailure = true;
+  }
+
+  /** Whether or not this job is failing because a job earlier in the chain failed. */
+  protected boolean isCascadingFailure() {
+    return this.cascadingFailure;
+  }
+
   /** Provides a default exponential backoff given the current run attempt. */
   protected final long defaultBackoff() {
     return BackoffUtil.exponentialBackoff(runAttempt + 1, RemoteConfig.getDefaultMaxBackoff());

app/src/main/java/org/thoughtcrime/securesms/jobmanager/JobController.java

@@ -145,7 +145,10 @@ class JobController {
         List<Job> dependents = onFailure(job);
         job.setContext(application);
         job.onFailure();
-        Stream.of(dependents).forEach(Job::onFailure);
+        for (Job child : dependents) {
+          child.markCascadingFailure();
+          child.onFailure();
+        }
         return;
       }
 

app/src/main/java/org/thoughtcrime/securesms/jobmanager/JobManager.java

@@ -535,18 +535,6 @@ public class JobManager implements ConstraintObserver.Notifier {
       return this;
     }
 
-    public Chain after(@NonNull Job job) {
-      return after(Collections.singletonList(job));
-    }
-
-    public Chain after(@NonNull List<? extends Job> jobs) {
-      if (!jobs.isEmpty()) {
-        this.jobs.add(0, new ArrayList<>(jobs));
-      }
-
-      return this;
-    }
-
     public void enqueue() {
       jobManager.enqueueChain(this);
     }