[NO ISSUE] Set logging level to WARN in MaterializingPipelinedPartition

- user model changes: no
- storage format changes: no
- interface changes: no

Details:
Failures in MaterializingPipelinedPartition can be due to many reasons
such as a job cancellation. WARN log level seems to be adequate for
such failures keeping ERROR for more critical failures.

Change-Id: I45f475afae114dc71d2d89d9deaab7f3b3c5a0b8
Reviewed-on: https://asterix-gerrit.ics.uci.edu/2832
Sonar-Qube: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: abdullah alamoudi <bamousaa@gmail.com>
Reviewed-by: Murtadha Hubail <mhubail@apache.org>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Contrib: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
diff --git a/hyracks-fullstack/hyracks/hyracks-control/hyracks-control-nc/src/main/java/org/apache/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java b/hyracks-fullstack/hyracks/hyracks-control/hyracks-control-nc/src/main/java/org/apache/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
index 29c2ff2..37f33a9 100644
--- a/hyracks-fullstack/hyracks/hyracks-control/hyracks-control-nc/src/main/java/org/apache/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
+++ b/hyracks-fullstack/hyracks/hyracks-control/hyracks-control-nc/src/main/java/org/apache/hyracks/control/nc/partitions/MaterializingPipelinedPartition.java
@@ -89,7 +89,7 @@
                 Thread thread = Thread.currentThread();
                 setDataConsumerThread(thread); // Sets the data consumer thread to the current thread.
                 try {
-                    thread.setName(MaterializingPipelinedPartition.class.getName() + pid);
+                    thread.setName(MaterializingPipelinedPartition.class.getName() + " " + pid);
                     FileReference fRefCopy;
                     synchronized (MaterializingPipelinedPartition.this) {
                         while (fRef == null && !eos && !failed) {
@@ -164,7 +164,7 @@
                         }
                     }
                 } catch (Exception e) {
-                    LOGGER.log(Level.ERROR, e.getMessage(), e);
+                    LOGGER.warn("Failure writing to a frame", e);
                 } finally {
                     setDataConsumerThread(null); // Sets back the data consumer thread to null.
                 }