title: Eclipse UI tests fail with gtk_init_check() on a Redhat Jenkins server
body: <p>When running Tycho UI tests for Eclipse on a Redhat server (6.7) via Jenkins, the Exception below occurs. I know that a graphical subsystem must be installed and running, but there seems to be something amiss with my setup. I already installed GTK via "yum groupinstall Desktop".</p>
  
  <pre><code>org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed]
      at org.eclipse.swt.SWT.error(SWT.java:4517)
      at org.eclipse.swt.widgets.Display.createDisplay(Display.java:908)
      at org.eclipse.swt.widgets.Display.create(Display.java:892)
      at org.eclipse.swt.graphics.Device.&lt;init&gt;(Device.java:156)
      at org.eclipse.swt.widgets.Display.&lt;init&gt;(Display.java:512)
      at org.eclipse.swt.widgets.Display.&lt;init&gt;(Display.java:503)
      at org.eclipse.ui.internal.Workbench.createDisplay(Workbench.java:790)
      at org.eclipse.ui.PlatformUI.createDisplay(PlatformUI.java:162)
      at org.eclipse.ui.internal.ide.application.IDEApplication.createDisplay(IDEApplication.java:169)
      at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:111)
      at org.eclipse.tycho.surefire.osgibooter.UITestApplication.runApplication(UITestApplication.java:31)
      at org.eclipse.tycho.surefire.osgibooter.AbstractUITestApplication.run(AbstractUITestApplication.java:115)
      at org.eclipse.tycho.surefire.osgibooter.UITestApplication.start(UITestApplication.java:37)
      at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
      at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
      at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
      at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
      at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:498)
      at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:669)
      at org.eclipse.equinox.launcher.Main.basicRun(Main.java:608)
      at org.eclipse.equinox.launcher.Main.run(Main.java:1515)
      at org.eclipse.equinox.launcher.Main.main(Main.java:1488)
  </code></pre>