MASSEMBLY-919: Fix dependency scope handling

[gzsombor]

The problem is that the assembly plugin collects every dependency, flatten the dependency hierarchy tree, and only after this, filter's out by scope. This will cause that if A has a test dependency B, which has a 'runtime' dependency C, C is treated as a runtime dependency of A, and it is included. The implemented fix is using proper tree walking, and checking eagerly the scope of the dependency.

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[struberg]

@gzsombor can you please help us draft an integration test first? I tried to replay your described scenario and I do not see any errors. Here is the code https://github.com/struberg/maven-assembly-plugin/tree/MASSEMBLY-919

Where does my IT differ from your use case?

[rfscholte]

I've replaced Easymock with Mockito, so this PR needs to be updated

[Geker]

any update ? this problem is still exists

[cstamas]

Ideally we need an IT (or some test) that reproduces the issue (fails the expectation) and then a PR that fixes it (makes IT pass).

@Geker can you provide a reproducer? or does https://github.com/apache/maven-assembly-plugin/pull/12#pullrequestreview-336128503 work?

[slawekjaranowski]

We should direct use Resolver API. By the way thanks for effort.