Fix undefined and default handling

demo/card.html

@@ -32,6 +32,11 @@
 							<paper-input value="{{value.last}}" style="display:inline-block;"></paper-input>
 						</template>
 					</paper-datatable-column>
+					<paper-datatable-column property="isAdmin" header="Administrator" default="false">
+						<template>
+							<paper-checkbox checked="{{value}}"></paper-checkbox>
+						</template>
+					</paper-datatable-column>
 				</paper-datatable>
 			</paper-datatable-card>
 
@@ -51,7 +56,8 @@
 					author: {
 						first: "David",
 						last: "Mulder "+ id
-					}
+					},
+					isAdmin: (Math.random() > 0.9 ? true : undefined)
 				});
 			}
 
@@ -70,6 +76,7 @@
 					});
 				},
 				set: function(id, property, value){
+					console.info("a save was triggered");
 					var item = myData.find(function(item){
 						return item.id == id;
 					});

paper-datatable-column.html

@@ -58,7 +58,7 @@
 					console.log(this.config);
 				},
 				createCellInstance: function(model, notificationId, notificationProp){
-					if(typeof model[this.property] == "undefined" && this.default){
+					if(typeof model[this.property] == "undefined" && typeof this.default !== "undefined"){
 						var instance = this.stamp({item: model, value: this.default, _dataId: notificationId});
 					}else{
 						var instance = this.stamp({item: model, value: model[this.property], _dataId: notificationId});

paper-datatable.html

@@ -283,9 +283,6 @@
 							}
 							if(cell.instance){
 								var instancePath = ["item", path.join(".")].join(".");
-								console.info(cell, "column", instancePath, "to", change.value);
-								console.info(cell.instance);
-								console.log(JSON.stringify(cell.instance.__data__));
 								cell.instance.notifyPath(instancePath, change.value, true);
 							}