Fix Undo button appearing as Disabled when it is enabled

Steps to reproduce:

• User navigates inside Web UI to a folder with content.
• User clicks on Spreadsheet Editor button
• User double-clicks on one of the cells under Title and changes the document's name but doesn't press enter
• With the cell still being edited, user right-clicks on it

Expected behaviour:

• Undo is Active and clickable

Actual behaviour:

• Undo works but is grey as if it was disabled

Rainforest Video in attachments (after 4'40'')