@NotNull
  private Pair<VcsRevisionNumber, byte[]> loadContent() throws VcsException {
    VcsRevisionNumber currentRevision = getCurrentRevisionNumber();
    ContentRevision contentRevision = myDiffProvider.createFileContent(currentRevision, myFile);

    if (contentRevision == null) {
      throw new VcsException(VcsBundle.message("changes.error.failed.to.create.content.for.current.revision"));
    }

    byte[] bytes;
    if (contentRevision instanceof ByteBackedContentRevision) {
      bytes = ((ByteBackedContentRevision)contentRevision).getContentAsBytes();
    }
    else {
      String content = contentRevision.getContent();
      if (content == null) throw new VcsException(VcsBundle.message("changes.error.can.t.get.revision.content"));
      bytes = content.getBytes(myFile.getCharset());
    }
    return Pair.create(currentRevision, bytes);
  }
@NotNull
  private Pair<VcsRevisionNumber, byte[]> loadContent()