Fix NPE in DetailsSection.languageChanged

!ENTRY org.eclipse.ui 4 0 2016-01-18 15:46:57.878
!MESSAGE Unhandled event loop exception
!STACK 0
java.lang.NullPointerException
	at org.apache.xerces.dom.ParentNode.internalRemoveChild(Unknown Source)
	at org.apache.xerces.dom.ParentNode.replaceChild(Unknown Source)
	at org.fusesource.ide.camel.editor.properties.DetailsSection.languageChanged(DetailsSection.java:1045)
	at org.fusesource.ide.camel.editor.properties.DetailsSection.access$2(DetailsSection.java:1019)
	at org.fusesource.ide.camel.editor.properties.DetailsSection$19.widgetSelected(DetailsSection.java:676)
	at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:248)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4362)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1113)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1137)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1122)
	at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:788)
	at org.eclipse.swt.custom.CCombo.listEvent(CCombo.java:1172)
	at org.eclipse.swt.custom.CCombo$1.handleEvent(CCombo.java:115)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4362)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1113)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4180)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3769)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1127)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1018)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:654)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:598)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:139)
	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(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	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)