Progress bar for Notepad IO

[kallanreed]

This is an attempt to add IO progress reporting for Notepad so it doesn't look hung when doing work.
There's still one long IO operation (the temp file copy) that looks like a hang.
Could add a progress callback on copy_file? I tried a paint hack to write a little warning before copying the file, but it caused an ISR stack overflow??

It doesn't help the edit scenario too much when files start getting large, but it's nice (especially on first open) to see an indicator that the device didn't fault.

[gullradriel]

LGTM

[kallanreed]

Loading a 4MB log file after this change, I'm seeing an M0 Guru fault in set_focus_widget when the progress bar reaches the end. The fault occurs if I start the Notepad app first, then press Select to open File Manager, and click on the file (fault occurs when progress bar reaches the end). If I start the File Manager app first, and click on the same file to open it in Notepad, it opens correctly (after the progress bar reaches the end).

Dang. What’s the Guru? SV#8?

[NotherNgineer]

Nevermind the comment about the Guru meditation fault after loading a huge file. It is related to the long file name, not to the progress bar.

[NotherNgineer]

I had been testing the feature to append the date to the file name, and the huge file name is what kills Notepad.

[NotherNgineer]

I've documented it in #1339 (LOWEST PRIORITY).