Bug 73656 Encoding: refactoring should flush the undo stack on encoding changes
Refactoring should flush the undo stack on encoding changes. It is questionable what to do if the encoding changes since the encoding has an impact on the number of characters. Alternativly the UndoTectFileChange could remember the encoding and could compare it in isValid(...).
org.eclipse.ltk.core.refactoring/src/org/eclipse/ltk/internal/core/refactoring/BufferValidationState.java
protected IFile fFile;
	protected boolean fExisted;
	protected static class ModificationStamp {
		private int fKind;
		private long fValue;
		public static final int FILE= 1;
		public static final int DOCUMENT= 2;
		
		public static ModificationStamp createFile(long value) {
			return new ModificationStamp(FILE, value);
		}
		public static ModificationStamp createDocument(long value) {
			return new ModificationStamp(DOCUMENT, value);
		}
		private ModificationStamp(int kind, long value) {
			fKind= kind;
			fValue= value;
		}
		public boolean isFileStamp() {
			return fKind == FILE;