Building with unity takes materials from random storages

Issue description

When I build something with unity that requires other materials than construction parts (eg. rubber, steel, glass), the game takes those materials from random storages around the island. This is problematic in builds that have storages of those materials in front of assemblers, as those needs to be then re-filled with trucks/conveyors/trains, potentially starving some parts of factory for a while and triggering alarms on those storages.

IMO, building with unity should only take materials from storages that allow export, or alternatively some specific order should be established: shipyard first, then storages with export enabled, then the other storages for example.

My specific build that I observed that issue:

• I have a large storages in place where goods are created from which I distribute it over factory using conveyors; this has export option enabled
• Additionally in front of every production unit, I have a small storages for every needed item with export disabled and alarms if below 50%

Reproduction steps

1. Build few storages of glass with different settings of export.
2. Build some greenhouses with unity and observe from which storage the glass is taken

Game version and build number

v0.8.4b (b593)

Operating system

Windows

According to my observations, the resources are taken from the storage that was built last.

According to my observations, the resources are taken from the storage that was built last.

Hmm, I think in my case it was more or less random.