<cr-shared-menu> forces iron-dropdown's allowOutsideScroll property on, meaning that after opening the dropdown menu, we can still scroll the page. The dropdown menu remains in a fixed position in the viewport, which is rarely what we want.

Example in chrome://md-settings: the 3-dot menus in "Autofill settings" open a cr-shared-menu which remains fixed on the screen when scrolling the page.

Potential solutions:

1. Prevent scrolling outside the dropdown.
2. Close the dropdown when scrolling outside the dropdown.
3. Position the dropdown absolute, so it scrolls with the container.