ONOS-6259: Topo2 - Implement server-side highlighting model (WIP)
- added locType parameter to region-add command
- created RegionABC sample topology
- fixed possible NPE in Topo2Jsonifier.jsonClosedRegion()
- added "plain" sprite layout
- check for undefined sprite layout and log a warning
- updated logger.sh script
- fixed Topo2Model to have a reference to colleciton before initialization

Change-Id: Ie6af28516338f5d64576bf465373cb5df3dff52c
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/Topo2Jsonifier.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/Topo2Jsonifier.java
index c7a223f..da1f8e4 100644
--- a/web/gui/src/main/java/org/onosproject/ui/impl/topo/Topo2Jsonifier.java
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/Topo2Jsonifier.java
@@ -611,9 +611,11 @@
         //       all descendant subregions.
 
         Region r = region.backingRegion();
-        // this is location data, as injected via network configuration script
-        addGeoGridLocation(node, r);
-        addProps(node, r);
+        if (r != null) {
+            // add data injected via network configuration script
+            addGeoGridLocation(node, r);
+            addProps(node, r);
+        }
 
         // this may contain location data, as dragged by user
         // (which should take precedence, over configured data)