Dreamfall Chapters: Add chapter 2 wall surface shader

Strangely I can't seem to match this one in the asset files (same goes
for other chapter 2 surface shaders). Perhaps the CRC32 calculation is
getting messed up for some shaders, perhaps I just missed it with Unity
Asset Explorer (side note - the .asset format looks pretty trivial to
decode myself, which would make this workflow easier), maybe it is
stored somewhere I haven't looked, or maybe it's generated on the fly?
Dreamfall Chapters: Fix chapter 2 wall surface shader