fix: invalidate counter visual (#338)

[gadfly3173]

Keep the same implementation as CommitRefsPresenter to avoid displaying the number of the previous DataContext

[love-linger]

CommitRefsPresenter depends on DataContext to draw contents. But CounterPresenter only depends on its own property CountProperty to draw contents.

static CounterPresenter()
{
    AffectsMeasure<CounterPresenter>(
        FontSizeProperty,
        FontFamilyProperty,
        ForegroundProperty,
        CountProperty);

    AffectsRender<CounterPresenter>(
        ForegroundProperty,
        BackgroundProperty,
        CountProperty);
}

The issue #338 still exists about this control?

[gadfly3173]

The issue #338 still exists about this control?

The current situation is that after switching repo, the number of the previous repo may be displayed. After making this change, I cannot reproduce the problem here.

[gadfly3173]

CommitRefsPresenter depends on DataContext to draw contents. But CounterPresenter only depends on its own property CountProperty to draw contents.

static CounterPresenter()
{
    AffectsMeasure<CounterPresenter>(
        FontSizeProperty,
        FontFamilyProperty,
        ForegroundProperty,
        CountProperty);

    AffectsRender<CounterPresenter>(
        ForegroundProperty,
        BackgroundProperty,
        CountProperty);
}

It seems that OnDataContextChanged can be removed.

[love-linger]

Since you have added the InvalidateVisual in the end of MeasureOverride, I suggest you to remove the CountProperty from AffectsRender call.

[gadfly3173]

Confirmed that AffectsRender can be all removed, change theme also would re-render this control.