Chrome Version: built from tip of tree
OS: linux

What steps will reproduce the problem?
(1) use a tiling window manager (i3, bspwm, xmonad, etc)
(2) open a picture-in-picture video
(3)

What is the expected result?
a video window opens near the bottom right of the screen

What happens instead?
The window manager forces a size change on the window.

I made a video detailing this (https://files.tedm.io/recording_1532638831.mp4)
You can see that when I set the video to picture in picture mode, it defaults to a large window on the left side; only after I tell my window manager to make it a floating window does it actually behave and go to the bottom right corner. Contrast this to the open-file dialog which is created as a floating window initially.

I'm willing to fix this if nobody has a tiling WM.