fix(label-editing): cancel on element deletion

Closes https://github.com/bpmn-io/bpmn-js/issues/1664

lib/features/label-editing/LabelEditingProvider.js

@@ -58,6 +58,16 @@ export default function LabelEditingProvider(
     }
   });
 
+  eventBus.on([
+    'shape.remove',
+    'connection.remove'
+  ], function(event) {
+
+    if (directEditing.isActive(event.element)) {
+      directEditing.cancel();
+    }
+  });
+
   // cancel on command stack changes
   eventBus.on([ 'commandStack.changed' ], function(e) {
     if (directEditing.isActive()) {

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

@@ -203,6 +203,26 @@ describe('features - label-editing', function() {
       }
     ));
 
+
+    it('should cancel on element deletion', inject(
+      function(elementRegistry, directEditing, selection, modeling) {
+
+        // given
+        var shape = elementRegistry.get('Task_1'),
+            task = shape.businessObject;
+
+        directEditing.activate(shape);
+
+        directEditing._textbox.content.textContent = 'FOO BAR';
+
+        // when
+        modeling.removeElements([ shape ]);
+
+        // then
+        expect(task.name).not.to.equal('FOO BAR');
+      }
+    ));
+
   });