Once milestone is released, an example how to take advantage of this feature will be described in the DSL reference:
http://gradle.org/current/docs/dsl/org.gradle.api.tasks.OutputSourceSet.html

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This will help us fix ToolingApiIntegrationTest so it can run in the IDE. While not strictly necessary to fix the test, it might be better in this case to fix Gradle, rather than add more workarounds to our build scripts (and those of everyone else who has generated resources).

For some discussion, see http://gradle.markmail.org/thread/2pwkcs7b7wuq4l2q. I think we should start with option 2, and then maybe look at adding option 4.