Tooltip: still shown even when element is not in the scrolled area anymore

[StefanKern]

Reproduction

Reproduziere in the standard demos of angular material.

The error only occurs when manually opening the Tooltip . I encounter it, because I'm building a custom Tooltip component, which is not closed/ on hover.

Steps to reproduce:

1. Open to https://material.angular.io/components/tooltip/examples
2. Navigate to the 'Tooltip that can be manually shown/hidden.' Demo.
3. Click "show"
4. scroll to the bottom of the page

Expected Behavior

When the element connected to the Tooltip leaves the visible leaves the tooltip should also disappear.

Actual Behavior

The tooltip is fixed at a position on top of the screen. However when scrolling up, it get's hidden. Also it goes over the navigation bar, where it should already be hidden.

Environment

• Angular: 8.0.0
• CDK/Material: 8.0.0
• Browser(s): Chrome
• Operating System (e.g. Windows, macOS, Ubuntu): Windows

[Totati]

For me when the window width is less than 721px the tooltip sticks to the top when I scroll down, and goes down when I scroll up - it stays open. When the window width is bigger than 720px, is sticks to the bottom when I scroll up, and fades when I scroll down.