Tweak download usability problems

[bbondy]

• Don't prompt for save location by default (make it a preference)
  
• Add a Show All button to the downloads toolbar.
• Only active state downloads should have a white background, completed state items should have a gray background.
  
• Show some kind of confirmation when a link is copied to the clipboard. I think using a web notification works here.
• Ask to confirm whether or not to delete an item after the trash can is clicked
• Show downloaded file size next to progress complete
• Downloads toolbar should only display new things since it was opened

CC @bradleyrichter

[Segment0895]

Sometimes a download is started but doesn't trigger the download bar. It happened at least twice but I've yet to find out how to trigger it on purpose.

[bbondy]

I think I've seen this before too. Once you're in this state can any download show it? Or only a browser restart fixes?

[Segment0895]

I think only a browser restart fixed it.
If it happens again, I'll report it.

[Segment0895]

Hasn't happen again.

[bbondy]

were you using a normal tab or was it a private tab / session tab? Thanks.

[bbondy]

Only active state downloads should have a white background, completed state items should have a gray background.

Fixed in 0.9.2

[bbondy]

Show some kind of confirmation when a link is copied to the clipboard. I think using a web notification works here.

Fixed for 0.9.3

[cndouglas]

Don't prompt for save location by default (make it a preference)

To prevent rogue websites from downloading tons of files, I think there should still be some sort of prompt.

[cndouglas]

Ask to confirm whether or not to delete an item after the trash can is clicked

Fixed in 0.13.5 with #7072.

[cndouglas]

Don't prompt for save location by default (make it a preference)

Fixed in 0.14.0 with #7023.