Shadows are much darker when using a baked GI then realtime light.

To reproduce:

1. Open scene "Realtime with No Bake.unity".

Note: Shadows appear correct.

2. Open scene "Realtime with Bake.unity"

Note: Shadows are twice as dark, indicating contribution from both lightmaps and realtime shadows.

Expected results: Shadows look similar.
Actual results: Shadows look very different.

Reproduces with: 5.5.0p3; 5.6.0b3 (shadows look more similar with this version);

Doesn't reproduce with: 5.3.6f1; 5.4.3p3; (shadows look exactly the same with these versions)

Note: Rerpo project for 5.3.6f1 is attached to this letter. (ShadowTest2)
Rerpo project for 5.4.3p3 is attached to this letter. (ShadowTest)