JobQueue: fixed incorrect requeuing.

* A dependent job was requeued even if it wasn't part of the queue
  before. The code relied on dependent jobs being already enqueued;
  but that cannot be guaranteed.
* If a job failed, its dependent jobs are now also set to failed, so
  that they won't be requeued at a later point.
* This caused some of the "Launching xxx failed: Operation not allowed"
  messages in the boot process. Those actually weren't harmless, and
  could mess up the natural job order.

headers/private/support/JobPrivate.h

@@ -30,6 +30,16 @@ public:
 		fJob._ClearTicketNumber();
 	}
 
+	void SetState(BJobState state)
+	{
+		fJob.SetState(state);
+	}
+
+	void NotifyStateListeners()
+	{
+		fJob.NotifyStateListeners();
+	}
+
 private:
 			BJob&				fJob;
 };

src/kits/support/JobQueue.cpp

@@ -243,16 +243,24 @@ void
 JobQueue::_RequeueDependantJobsOf(BJob* job)
 {
 	while (BJob* dependantJob = job->DependantJobAt(0)) {
-		try {
-			fQueuedJobs->erase(dependantJob);
-		} catch (...) {
+		JobPriorityQueue::iterator found = fQueuedJobs->find(dependantJob);
+		bool removed = false;
+		if (found != fQueuedJobs->end()) {
+			try {
+				fQueuedJobs->erase(dependantJob);
+				removed = true;
+			} catch (...) {
+			}
 		}
 		dependantJob->RemoveDependency(job);
-		try {
-			fQueuedJobs->insert(dependantJob);
-			if (dependantJob->IsRunnable())
-				release_sem(fHaveRunnableJobSem);
-		} catch (...) {
+		if (removed) {
+			// Only insert a job if it was in our queue before
+			try {
+				fQueuedJobs->insert(dependantJob);
+				if (dependantJob->IsRunnable())
+					release_sem(fHaveRunnableJobSem);
+			} catch (...) {
+			}
 		}
 	}
 }
@@ -266,8 +274,15 @@ JobQueue::_RemoveDependantJobsOf(BJob* job)
 			fQueuedJobs->erase(dependantJob);
 		} catch (...) {
 		}
+
+		if (dependantJob->State() != B_JOB_STATE_ABORTED) {
+			BJob::Private(*dependantJob).SetState(B_JOB_STATE_ABORTED);
+			BJob::Private(*dependantJob).NotifyStateListeners();
+		}
+
 		_RemoveDependantJobsOf(dependantJob);
 		dependantJob->RemoveDependency(job);
+		// TODO: we need some sort of ownership management
 		delete dependantJob;
 	}
 }