Expose ProjectRunnable#toString to set the thread name in core

Setting a proper toString message will allow Gerrit core to
include the message in the thread name which makes debugging
easier.

Change-Id: Ie874ca95ee6f74352cf161cd4ebecd9e00ec9045
diff --git a/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/RefUpdateListener.java b/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/RefUpdateListener.java
index 311a808..d18d1df 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/RefUpdateListener.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/reviewnotes/RefUpdateListener.java
@@ -80,7 +80,7 @@
 
           @Override
           public String toString() {
-            return "create-review-notes";
+            return "create-review-notes-for-" + e.getProjectName();
           }
         };
     if (async) {