Animation timeline shows black when only animating the opacity of a widget (regardless of the the color setting in that widget)

This is something that needs to be solved at the color track level in sequencer, we need to be showing current values in place of 0,0,0 for the things that are not animated.

When animating just the opacity setting of a widget, the color shown in the timeline defaults to black even if the color of the widget is not black.

1. Open Editor
2. Create a new widget blueprint
3. Add a Text block to the designer tab
4. Set the color of the text to Red in the details panel
5. Create a new animation
6. Create an animation that's opacity fades out over 3 seconds
7. Removed all keys on the timeline used to set the color of the widget
8. Notice that even though the widget is still red that the time line show the color to be black

Expected: The time line would should the current color of the widget being faded out
Result: The animation looks as though the widget is fading out from black