SendKeysToElement should only scrollIntoView if the element is not visible
Element Send Keys states that the commands scrolls into view the element and then sends the keys.
https://www.w3.org/TR/webdriver2/#element-send-keys
The definition for this scroll into view, found at https://www.w3.org/TR/webdriver2/#dfn-scrolls-into-view, states that
the element should only be scrolled into view if the element is not already scrolled into view.
The patch checks whether the element is visible before scrolling it into view.
Differential Revision: https://phabricator.services.mozilla.com/D215719
bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1906095
gecko-commit: f44e58d04deb48fe17d99044fce53c92f11906e5
gecko-reviewers: webdriver-reviewers, jdescottes