Merge branch 'master' into stable-3.5

* master:
  TaskTree: remove 'ERROR:' prefix from log statement
  TaskTree: fix errorprone warning about Flogger

Most development has happened in the stable-3.5 branch, but master has a
couple commits missing from there. Merge them in before creating new
stable branches based on stable-3.5.

Change-Id: I0698db5f5cdadb5b208fdac09e0a4ffece20b2d0

src/main/java/com/googlesource/gerrit/plugins/task/TaskTree.java

@@ -473,7 +473,7 @@ task.config.new Task(tasksFactory, changeData.getId().toString())),
             return;
           }
         } catch (StorageException e) {
-          log.atSevere().withCause(e).log("ERROR: running changes query: %s", namesFactory.changes);
+          log.atSevere().withCause(e).log("Running changes query '%s' failed", namesFactory.changes);
         } catch (QueryParseException | ConfigInvalidException e) {
         }
         addInvalidNode();