This patch turns the options of the Color Balance node into inputs.
In the process, each of the wheels were split into two inputs, a base
float and a color. For instance, Gain is controlled using both a Base
Gain and Color Gain, the former controls the gain for all channels while
the latter controls it per channel.
Reference #137223.
Pull Request: https://projects.blender.org/blender/blender/pulls/138610
6c62fb5ff6