test(Viewer): split config -> container handling into own describe

test/spec/ViewerSpec.js

@@ -589,7 +589,10 @@ describe('Viewer', function() {
 
     });
 
-    it('should attach the viewer to the given parent', function(done) {
+
+    describe('container', function() {
+
+      it('should attach if provided', function(done) {
 
         var xml = require('../fixtures/bpmn/simple.bpmn');
 
@@ -603,7 +606,8 @@ describe('Viewer', function() {
         });
       });
 
-    it('should not attach the viewer automatically if no parent was given', function(done) {
+
+      it('should not attach if absent', function(done) {
 
         var xml = require('../fixtures/bpmn/simple.bpmn');
 
@@ -616,6 +620,9 @@ describe('Viewer', function() {
           done(err, warnings);
         });
       });
+
+    });
+
   });