Add support for the HSL color format to the new color picker.

Prior to this CL, the new color picker supported the HEX and RGB color
formats. Now, users can also view and/or manually change the selected
color in the HSL color format.

Users can switch between the HEX, RGB and HSL by clicking on the format
toggler. To make it easier to translate values from one format to
another, additional helper functions like rgbToHSL and hslToHex are
being added to the Color class.
Update hex format toggle test and add hsl format toggle test.

Change-Id: I7a215af1788018c5a895b76c71a02c9aeeb987bd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1731777
Reviewed-by: Mason Freed <masonfreed@chromium.org>
Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Sanket Joshi <sajos@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#684033}
15 files changed