Persisting font size between Brackets Sessions

Here is the code to persist font size between Brackets Sessions per this discussion:

https://groups.google.com/forum/#!topic/brackets-dev/rYDR13sbhnk

In addition, I noticed a bug where the Increase, Decrease, and Restore Font Size commands remain enabled when there is no current document open in the editor.  When I executed the commands, it threw errors into the Dev Tools console.

I fixed the bug but there is still a small problem I can't figure out.  When the commands are disabled, I am still able to use the shortcut key for Decrease Font Size (Ctrl--) and throw a different error into the Dev Tools console.  I don't know why it is still firing off after I disabled the command.  Doesn't happen with the other two disabled commands.  Any assistance or insight on this problem would be appreciated.

-- Lance.