Unused asset (in this case - texture) is added to Configure list as if it will go to an Asset Bundle (but it will not).

Steps to reproduce:
1. Open attached project (demo.zip)
2. Create a New material (Shader = Standart)
3. Change Assets/unity.png Texture Type to "Normal map"
4. Open Assets/New Material and change Normal map to Assets/unity.png
5. Change Shader to Unlit > Color (so the material would become white). At this point Assets/New Material is expected not to be added to the Asset bundle
6. Add New Material to a new Asset Bundle "testbundle"
7. Window > AssetBundle Browser > Build > Build
8. Window > AssetBundle Browser > Configure

Expected behavior: no "unity.png" entry as it was not used in New Material after performing step 5.
Actual result: there is "unity.png" entry. However, if we open Window > AssetBundle Browser > Inspect, we can see that "unity.png" was not added to "tesbundle".

Reproduced with: 5.6.3f1, 2017.1.0p5, 2017.2.0b8.

Note:
Get Unity Asset Bundle Browser tool here: https://docs.unity3d.com/Manual/AssetBundles-Browser.html