I will work on the UI. 

Here is the spec for the overscan UI.

Here are the assets for the screen.
https://drive.google.com/open?id=0B_2Uyb2Rhx2OdjFUVmEtM29iQnc

Mocks:
https://drive.google.com/open?id=0B_2Uyb2Rhx2OZUFRNnZYRUNZNW8

Deleted: 0.1 - Overscan UI Spec.jpg 895 KB

	0.1 - Overscan UI Spec.jpg 895 KB View Download

The mock shows Overscan as a subpage.

Currently it is implemented as a dialog, which is simpler for the following reasons:
1. A subpage can be directly navigated to; a dialog can not. Navigating directly to the overscan adjustment page is not always valid and may have problematic edge cases.
2. We have to be very careful about ensuring that the overscan adjustment overlay gets removed when we close the dialog. I just fixed a bug related to this and I am concerned that subpage navigation may make managing the overlay more difficult.

For now I have fixed the text and some spacing, but left this as a dialog with the Reset and OK (was Save) buttons on the right. This is standard formatting for all Settings dialogs. The Cancel button is the dialog close button.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/857d7966566652606eebaf44e27db67f36d3d0dc

commit 857d7966566652606eebaf44e27db67f36d3d0dc
Author: stevenjb <stevenjb@chromium.org>
Date: Thu Dec 29 00:20:49 2016

MD Settings: Display > Overscan: Update text and fix focus

While updating the text I discovered that changing the focus (e.g. by calling blur() on the focused button, or simply clicking or tabbing away from the dialog) would cause the keyboard event to not get triggered. This change was introduced in https://codereview.chromium.org/2180823004.

The simple fix is to call window.addEventListener instead of this.addEventListener.

BUG= 660597 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2589353002
Cr-Commit-Position: refs/heads/master@{#440910}

[modify] https://crrev.com/857d7966566652606eebaf44e27db67f36d3d0dc/chrome/app/settings_strings.grdp
[modify] https://crrev.com/857d7966566652606eebaf44e27db67f36d3d0dc/chrome/browser/resources/settings/device_page/display_overscan_dialog.html
[modify] https://crrev.com/857d7966566652606eebaf44e27db67f36d3d0dc/chrome/browser/resources/settings/device_page/display_overscan_dialog.js
[modify] https://crrev.com/857d7966566652606eebaf44e27db67f36d3d0dc/chrome/browser/ui/webui/settings/md_settings_localized_strings_provider.cc