addressing PR comments

Author: abstractdog

tez-common/src/main/java/org/apache/tez/common/AsyncDispatcher.java

@@ -196,6 +196,9 @@ protected void dispatch(Event event) {
       } else {
         throw new Exception("No handler for registered for " + type);
       }
+    } catch (InterruptedException ie) {
+      LOG.warn("Interrupted Exception while handling event: " + event.getType(), ie);
+      Thread.currentThread().interrupt();
     } catch (Throwable t) {
       LOG.error("Error in dispatcher thread", t);
       // If serviceStop is called, we should exit this thread gracefully.