Code review comment for lp:~dandrader/mir/switchingBundle_lp1270964

(1) The new test fails:
[ RUN ] SwitchingBundleTest.compositor_client_interleaved
/home/dan/bzr/mir/tmp.964/tests/unit-tests/compositor/test_switching_bundle.cpp:389: Failure
Value of: bundle.first_ready
  Actual: 1
Expected: 0
[ FAILED ] SwitchingBundleTest.compositor_client_interleaved (0 ms)
The same failure is occurring on desktop amd64 and armhf (Nexus 10).

(2) I'm undecided about this approach:
47 + friend class SwitchingBundleTest_compositor_client_interleaved_Test;
It's certainly a convenient solution for introspection. But that then allows the test to couple to internal members it shouldn't be coupled to.

And before anyone asks, this has nothing to do with bug 1270245 (which still happens with this branch).