@Override
  @Nullable
  public AnnotationSourceSwitcher getAnnotationSourceSwitcher() {
    if (!myShowMergeSources) return null;
    return new AnnotationSourceSwitcher() {
      @Override
      @NotNull
      public AnnotationSource getAnnotationSource(int lineNumber) {
        return myInfos.getAnnotationSource(lineNumber);
      }

      @Override
      public boolean mergeSourceAvailable(int lineNumber) {
        return myInfos.mergeSourceAvailable(lineNumber);
      }

      @Override
      @NotNull
      public LineAnnotationAspect getRevisionAspect() {
        return ORIGINAL_REVISION_ASPECT;
      }

      @Override
      @NotNull
      public AnnotationSource getDefaultSource() {
        return AnnotationSource.getInstance(myShowMergeSources);
      }

      @Override
      public void switchTo(AnnotationSource source) {
        myInfos.setShowMergeSource(source.showMerged());
      }
    };
  }
@Override
  @Nullable
  public AnnotationSourceSwitcher getAnnotationSourceSwitcher()