Input preferences: Use BControlLook::ComposeIconSize().

And do some other cleanup while at it.

Fixes #17919.

input preferences: Updates code according to Haiku guidelines

These are the changes using tool clang-format with argument --style=haiku and the changes that were not according to guidelines have been removed.

Change-Id: I2d34370e1e0a112da895001bd220bb82b7086e90
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3827
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Input preferences: fix list minimum size

- Use the longest device name as a min size
- Refactor things a bit to simplify the code
- Also set weights in the top group view to ensure a nice ratio between
the list and the other part of the window

Input: add icons to the DeviceList

Change-Id: I2eaebca0f0e91e3420b7e63a4a568f4e658af253
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2722
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Input preferences: Make Device list width is font sensitive

Fixes #15738

Change-Id: I125c47f015c939acbd70c9509310ec3cdef7d2c5
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2308
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Connected Devices: Mouse, Touchpad and Keyboard

-Resolve some issues.
-Added the connected devices code in the main window.
-Replace BUTTON_DEFAULTS and BUTTON_REVERT with kMsgDefaults and kMsgRevert.

Change-Id: I3b0c86fc581056859239df0fbf2c085b8d168136
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1619
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Input: improve layout

Put some margins around the main view

Input preferences: fix build

One file was accidentally missing from this commit and was added to the
next one (which isn't ready for merging yet). Add it back here instead.