Asset references not restored correctly on editor hot reload

Release Type: Github

Describe the bug
If Component A has a reference to an asset and Component B references Component A then the asset will be null when accessed in a processor for Component B after the editor has hot reloaded the assembly.

It seems that Component B references an old copy of Component A after reload, breaking in the debugger shows that the correct instance exists in the EntityManager but not in the component reference.

To Reproduce

1. Create a component that references any asset, for example a Model.
2. Create a second component that references the first
3. Create a processor that loops through the second component types and uses the Model from the referenced component
4. Add an entity with the first component type and set a reference to an asset
5. Add an entity with the second component type and set a reference to the first component
6. Re-save any script so that the editor hot reloads the assembly
7. You will now get a null exception.

Additional context
A sample project that reproduces the issue can be found here: https://onedrive.live.com/?authkey=%21AE%2DOVsio9OJ13HE&id=AB3F11B2CDEC1EB4%21278400&cid=AB3F11B2CDEC1EB4

Adding a space to the script in the sample project and saving should cause the editor show a null exception after hot reload.

Hope I make sense, it's a bit difficult to describe :)

Start with the linked sample project and reproduce the failure by adding a space to a script and saving it to trigger editor hot reload. Trace how component references are restored during assembly reload, focusing on why Component B retains an old copy of Component A. Done means the asset remains accessible through the referenced component in the processor after reload, without the null exception.