Fixed the watermark of the vertical bars graph

(cherry picked from commit 12d7087014)

pandora_console/include/graphs/flot/pandora.flot.js

@@ -465,6 +465,10 @@ function pandoraFlotHBars(graph_id, values, labels, water_mark,
 		}
 		return format;
 	}
+	
+	if (water_mark) {
+		set_watermark(graph_id, plot, $('#watermark_image_'+graph_id).attr('src'));
+	}
 }
 
 var previousPoint = null, previousLabel = null;