Bug 86135 Make use of new IResource#revertModificationStamp(long) API
org.eclipse.ltk.core.refactoring/src/org/eclipse/ltk/internal/core/refactoring/BufferValidationState.java
protected static boolean isDirty(IFile file) {
		ITextFileBuffer buffer= getBuffer(file);
		if (buffer == null)
			return false;
		return buffer.isDirty();
	}
	
	protected static ITextFileBuffer getBuffer(IFile file) {
		ITextFileBufferManager manager= FileBuffers.getTextFileBufferManager();
		IPath path= file.getFullPath();
		ITextFileBuffer buffer= manager.getTextFileBuffer(path);
		return buffer;
	}
}
class DirtyBufferValidationState extends BufferValidationState {
	
	private IDocumentListener fDocumentListener;
	private FileBufferListener fFileBufferListener;
	private boolean fChanged;
	private ContentStamp fContentStamp= null;
	
	class DocumentChangedListener implements IDocumentListener {
		public void documentAboutToBeChanged(DocumentEvent event) {
		}
		public void documentChanged(DocumentEvent event) {
			DirtyBufferValidationState.this.documentChanged();
		}
	}
	
	class FileBufferListener implements IFileBufferListener {