Patch Set 2: I would prefer that you didn't submit this; IP review completed

Very cool. What's missing are some UI tests. For a start, you may want to have a look at GitRepositoriesViewTest.testImportWizard(). If you simply copy this to, say, testImportWizardWithWorkingSet(), you should be able to do the job. I think verification that the new project is in fact in the expected working set could be done using the API IWorkingSet.getElements(), i.e. no check if the project explorer shows the hierarchy or such.
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