Test failures on OS X

This problem was here starting from migration to Tycho, but now I have a Mac to investigate it.
```
-------------------------------------------------------------------------------
Test set: com.mountainminds.eclemma.internal.core.analysis.TypeTraverserTest
-------------------------------------------------------------------------------
Tests run: 1, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 2.044 sec <<< FAILURE!
testTraverse1(com.mountainminds.eclemma.internal.core.analysis.TypeTraverserTest)  Time elapsed: 2.043 sec  <<< FAILURE!
junit.framework.AssertionFailedError: Unbound classpath container: 'Default System Library' in project 'UnitTestProject'
        at junit.framework.Assert.fail(Assert.java:47)
        at junit.framework.Assert.assertTrue(Assert.java:20)
        at com.mountainminds.eclemma.core.JavaProjectKit.assertNoErrors(JavaProjectKit.java:214)
        at com.mountainminds.eclemma.internal.core.analysis.TypeTraverserTest.setup(TypeTraverserTest.java:66)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
        at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
        at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:27)
        at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
        at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
        at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
        at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
        at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
        at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
        at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
        at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
        at org.apache.maven.surefire.junit4.JUnit4TestSet.execute(JUnit4TestSet.java:53)
        at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:123)
        at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:104)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:164)
        at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:110)
        at org.apache.maven.surefire.booter.SurefireStarter.invokeProvider(SurefireStarter.java:175)
        at org.apache.maven.surefire.booter.SurefireStarter.runSuitesInProcess(SurefireStarter.java:123)
        at org.eclipse.tycho.surefire.osgibooter.OsgiSurefireBooter.run(OsgiSurefireBooter.java:84)
        at org.eclipse.tycho.surefire.osgibooter.HeadlessTestApplication.run(HeadlessTestApplication.java:21)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.eclipse.equinox.internal.app.EclipseAppContainer.callMethodWithException(EclipseAppContainer.java:574)
        at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:368)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:559)
        at org.eclipse.equinox.launcher.Main.basicRun(Main.java:514)
        at org.eclipse.equinox.launcher.Main.run(Main.java:1311)
        at org.eclipse.equinox.launcher.Main.main(Main.java:1287)
```