Sidebar's On mouseover option doesn't work with right side sidebar

[simonhong]

Description

Steps to Reproduce

1. Set sidebar on right
2. Set On mousever as a sidebar show option
3. Move mouse to the right side of brower window

Actual result:

Sidebar is not shown

Expected result:

it should be shown

Reproduces how often:

Easy

Brave version (brave://version info)

Version/Channel Information:

• Can you reproduce this issue with the current release? No
• Can you reproduce this issue with the beta channel? Yes
• Can you reproduce this issue with the nightly channel? Yes

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
• Does the issue resolve itself when disabling Brave Rewards?
• Is the issue reproducible on the latest version of Chrome?

Miscellaneous Information:

[kjozwiak]

The above requires 1.46.81 or higher for 1.46.x verification 👍

[stephendonner]

Verified PASSED using

Brave	1.46.81 Chromium: 107.0.5304.68 (Official Build) beta (x86_64)
Revision	a4e93e89d3b3df1be22214603fba846ad0183ca5-refs/branch-heads/5304@{#991}
OS	macOS Version 11.7.1 (Build 20G918)

Steps:

1. installed 1.46.81
2. launched Brave
3. opened brave://settings/appearance
4. set Show Sidebar to On mouseover
5. set Side panel to Show on right
6. hovered over the right side of the browser window
7. move the pointer away from the right side

Confirmed the sidebar appeared only on mouseover on the right, and disappeared on mouse-away

brave://settings/appearance	On mouseover