Bug: save crash

[jacob-z]

Running trellis through R Studio, clicking on save crashed the program (main branch).

`[1] "Warning while loading file"

Warning: Error in if: argument is of length zero
73: save
72: observeEventHandler [trellis/src/shiny/server.R#203]
1: runApp`

[AFriendlyRobot]

Does the same codebase crash on save when run through the terminal? If not, are the R versions the same on terminal and RStudio?

[AFriendlyRobot]

@jacob-z Are you able to check whether this still occurs in the current master branch? A lot of structure has changed with the optimization updates. At the same time, it looks like shinyFiles updated and has added some new features and some new bugs.
I'm not sure how to try replicating this, but please let me know if you can replicate consistently.

[AFriendlyRobot]

Removing from 1.0 milestone until verified.