> Also, I'm not sure that we need an evictable cache here. This cache holds info about assets, AssetInfo looks like it will be about 200 bytes in size, a big project might have 1000 assets, that's only 200kb of meta data to store.

One thing to keep in mind here is that given WebJars a whole swag of dependencies may come in. Thus I think it is possible to have a 1000 assets. Check out the angularjs webjar for a sample of many js files.