chore(label-editing): remove businessObject name on empty text

The following two actions will now unset the
business objects name property:

* deleting external label
* entering empty text via direct editing

lib/features/label-editing/LabelEditingProvider.js

@@ -370,6 +370,10 @@ LabelEditingProvider.prototype.update = function(
     };
   }
 
+  if (isEmptyText(newLabel)) {
+    newLabel = null;
+  }
+
   this._modeling.updateLabel(element, newLabel, newBounds);
 };
 
@@ -392,3 +396,7 @@ function isCollapsedPool(element) {
 function isExpandedPool(element) {
   return is(element, 'bpmn:Participant') && isExpanded(element);
 }
+
+function isEmptyText(label) {
+  return !label || !label.trim();
+}

lib/features/modeling/behavior/LabelBehavior.js

@@ -94,7 +94,7 @@ export default function LabelBehavior(
 
     // check if label
     if (labelTarget && hints.unsetLabel !== false) {
-      modeling.updateLabel(labelTarget, '', null, { removeShape: false });
+      modeling.updateLabel(labelTarget, null, null, { removeShape: false });
     }
   });
 

test/spec/features/label-editing/LabelEditingProviderSpec.js

@@ -244,6 +244,38 @@ describe('features - label-editing', function() {
     });
 
 
+    describe('should unset', function() {
+
+      it('name on empty text', function() {
+
+        // given
+        var diagramElement = elementRegistry.get('SequenceFlow_1');
+
+        // when
+        directEditActivate(diagramElement);
+        directEditComplete(' ');
+
+        // then
+        expect(diagramElement.businessObject.name).not.to.exist;
+      });
+
+
+      it('text on empty text', function() {
+
+        // given
+        var diagramElement = elementRegistry.get('TextAnnotation_1');
+
+        // when
+        directEditActivate(diagramElement);
+        directEditComplete(' ');
+
+        // then
+        expect(diagramElement.businessObject.text).not.to.exist;
+      });
+
+    });
+
+
     describe('should trigger redraw', function() {
 
       it('on shape change', function() {

test/spec/features/modeling/behavior/LabelBehaviorSpec.js

@@ -328,7 +328,7 @@ describe('behavior - LabelBehavior', function() {
 
       // then
       expect(startEventShape.label).not.to.exist;
-      expect(startEvent.name).to.equal('');
+      expect(startEvent.name).not.to.exist;
     }));
 
   });