UserAgent: Mozilla/5.0 (X11; CrOS aarch64 9202.43.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.85 Safari/537.36
Platform: 9202.43.0 (Official Build) beta-channel kevin

Steps to reproduce the problem:
1. Right click desktop >
2. Shelf position >
3. View 3 Choices (4th obvious is missing)

What is the expected behavior?
To right-click desktop > Shelf position > to see Bottom, Left, Right, and [Top]? Those expecting reasonable control over their interface will want to see the bar on top as an option. End user might be confused or agitated that an obvious 4th choice was omitted for no apparent reason.

What went wrong?
To right-click desktop > Shelf position > and see Bottom, Left, Right and no Top. Linux users have had this option forever. Depriving users of such a simple option is useless. Please give the user the option to put the Shelf where they want to regardless of design formality. The user will respect you more for providing them will all of the options. -CR

Did this work before? No 

Chrome version: 57.0.2987.85  Channel: beta
OS Version: 9202.43.0
Flash Version: Shockwave Flash 24.0 r0

Chrome OS is a masterpiece. Keep up your amazing work. -CR