GUI: attempt at handling errors properly

Errors in occuring in jIO are silently ignored because there many error
paths are missing in promise chain

dream/platform/src/dream/Input_viewProductionLine.js

@@ -62,13 +62,18 @@
       // We are notified by an included gadget that the data has changed.
       // Here we save automatically. We could mark a dirty flag to warn the
       // user if she leaves the page without saving.
-
+      return new RSVP.Queue()
+        .push(function() {
+          return RSVP.delay(100);
+        }).push(saveGraph.bind(this));
+        /*
       // Since we are notified quite often and saving is resource expensive, we
       // use this trick to prevent saving too many times
       if (this.timeout) {
         window.clearTimeout(this.timeout);
       }
       this.timeout = window.setTimeout(saveGraph.bind(this), 100);
+      */
     })
 
     .declareMethod("render", function (options) {
@@ -91,7 +96,7 @@
           return gadget.getDeclaredGadget("productionline_toolbox");
         })
         .push(function (toolbox_gadget) {
-          toolbox_gadget.render(data);
+          return toolbox_gadget.render(data);
         });
     })
 

dream/platform/src/jsplumb/jsplumb.js

@@ -145,7 +145,7 @@
       edge_data.destination = getNodeId(gadget, connection.targetId);
       gadget.props.data.graph.edge[connection.id] = edge_data;
     }
-    gadget.notifyDataChanged();
+    return gadget.notifyDataChanged();
   }
 
   function convertToAbsolutePosition(gadget, x, y) {
@@ -291,7 +291,7 @@
       }
     });
 
-    gadget.notifyDataChanged();
+    return gadget.notifyDataChanged();
   }
 
   function updateElementData(gadget, node_id, data) {
@@ -321,7 +321,7 @@
         }
       });
     }
-    gadget.notifyDataChanged();
+    return gadget.notifyDataChanged();
   }
 
   function addEdge(gadget, edge_id, edge_data) {
@@ -689,14 +689,14 @@
   function waitForConnection(gadget) {
     return loopJsplumbBind(gadget, 'connection',
                     function (info, originalEvent) {
-        updateConnectionData(gadget, info.connection, false);
+        return updateConnectionData(gadget, info.connection, false);
       });
   }
 
   function waitForConnectionDetached(gadget) {
     return loopJsplumbBind(gadget, 'connectionDetached',
                     function (info, originalEvent) {
-        updateConnectionData(gadget, info.connection, true);
+        return updateConnectionData(gadget, info.connection, true);
       });
   }
 
@@ -774,8 +774,7 @@
         { isTarget:true, maxConnections: -1 },
         { anchor: "LeftMiddle", uuid: node_id + ".flowChartLeftMiddle" });
 
-
-    gadget.notifyDataChanged();
+    return gadget.notifyDataChanged();
   }
 
   function waitForDrop(gadget) {