Bug 99886 [package explorer] Package Explorer focus is not synchronized with the active editor part
During startup Package Explorer tree is closed regardless of the editor currently opened.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
private boolean inputIsSelected(IEditorInput input) {
		IStructuredSelection selection= (IStructuredSelection)fViewer.getSelection();
		if (selection.size() != 1) 
			return false;
		IEditorInput selectionAsInput= null;
		try {
			selectionAsInput= EditorUtility.getEditorInput(selection.getFirstElement());
		} catch (JavaModelException e1) {
			return false;
		}
		return input.equals(selectionAsInput);
	}
	boolean showInput(Object input) {
		Object element= null;
			
		if (input instanceof IFile && isOnClassPath((IFile)input)) {
			element= JavaCore.create((IFile)input);
		}
				
		if (element == null) 
			element= input;
				
		if (element != null) {
			ISelection newSelection= new StructuredSelection(element);
			if (fViewer.getSelection().equals(newSelection)) {
				fViewer.reveal(element);
			} else {
				try {
					fViewer.removePostSelectionChangedListener(fPostSelectionListener);						
					fViewer.setSelection(newSelection, true);