Regression: Component properties box is blank when allowCreation is set to true

To reproduce, using Go Green:

• Open the file: SimpleDocumentParamsInfo.java
• Check that the DocumentLink annotation has parameter allowCreation = true
• Start the CMS and log in
• Go to the Channel Manager, edit mode
• Go to the Products section
• Click the "Welcome" component to open the component properties box
  Expected result: The component properties show in the box
  Actual result:
• The component properties box only displays the buttons
• The 'spinner' in the top left doesn't stop spinning
• Script error:
  Uncaught TypeError: Cannot call method 'on' of null page-editor-all.js:2320

In 7.7 the component properties box does show