WPF - OnLostMouseCapture with active scrolling.

- **What version of the product are you using?**
v85.3.130

- **What architecture x86 or x64?**
Both

- **On what operating system?**
Win10

- **Are you using `WinForms`, `WPF` or `OffScreen`?**
WPF

- **What steps will reproduce the problem?**
1)Draging the scrollbar with left button pressing
2)move the cursor out of the browser control
2)press alt+tab, choose other app.
3)release left button.
4)move mouse in browser, browser is thinking that mouse is pressed.

- **Please provide any additional information below.**
As i said in https://github.com/cefsharp/CefSharp/pull/2871 we have problem with OnLostMouseCapture.
Default wpf implementation does not raise mouse up event after lost mouse capture.

Worked fast fix(SubClass):
```
private bool isLeftMouseDown;
protected override void OnMouseDown(MouseButtonEventArgs e)
{
isLeftMouseDown = e.LeftButton == MouseButtonState.Pressed;
base.OnMouseDown(e);
}

protected override void OnLostMouseCapture(MouseEventArgs e)
{
var modifiers = e.GetModifiers();
var point = e.GetPosition(this);

if (isLeftMouseDown)
{
GetBrowser().GetHost().SendMouseClickEvent((int)point.X, (int)point.Y, MouseButtonType.Left, true, 1, modifiers);
isLeftMouseDown = false;
}

base.OnLostMouseCapture(e);
}
```

Riproduci lo scenario WPF descritto: trascina la barra di scorrimento, sposta il cursore fuori dal controllo del browser, passa da un’applicazione all’altra con Alt+Tab, rilascia il pulsante e muovi nuovamente il mouse. Inizia dalla gestione di OnLostMouseCapture in WPF e dal workaround mostrato nell’issue; il lavoro è completato quando il browser non considera più premuto il pulsante sinistro del mouse dopo la perdita della cattura.

Scritto dal modello di indicizzazione a partire dal testo della issue.