Use ResizeObserver when available for better and more performant resizing information, otherwise, fall back to a throttled resize event on an iframe that's the size of the player.
Allows a video.js user to disable this by setting resizeManager: false as an option since the component will not be initialized.
Add a debounce util.
This reverts #4800 (e0ed0b5) because we end up getting two playerresize events with the dimension methods now.
Internally uses the VolumeControl and MuteToggle components to create the VolumePanel component. Acts like the old VolumeMenuButton but does not have the screen reader issues of the older version.
BREAKING CHANGE: remove VolumeMenuButton, introduce a new default volume control: VolumePanel.
Switch to `keepTooltipsInside` by default and simplify DOM structure around the time tooltips and progress control.
BREAKING CHANGE: removal of `keepTooltipsInside` option.
