Google Chrome	53.0.2773.0 (Official Build) dev (64-bit)
Revision	0
Platform	8517.0.0 (Official Build) dev-channel samus-cheets

Please specify Cr-* of the system to which this bug/feature applies (add
the label below).

Steps To Reproduce:
1. Open wallpaper window.
2. Switch to overview mode.


Expected Result:

Actual Result:
Seen two close buttons.
But settings window have one close button.

How frequently does this problem reproduce? (Always, sometimes, hard to
reproduce?)

What is the impact to the user, and is there a workaround? If so, what is
it?

Please provide any additional information below. Attach a screen shot or
log if possible.
attached screenshot