"targetavailabilitychanged" event fired even when media element has disabledRemotePlayback = true

[jernoble]

f958006ab842501cad67547605411074e64e1610

"targetavailabilitychanged" event fired even when media element has disabledRemotePlayback = true
https://bugs.webkit.org/show_bug.cgi?id=274220
rdar://128137977

Reviewed by NOBODY (OOPS!).

The expectation is that `disableRemotePlayback = true` should cause all remote playback
events to not fire. Instead, disabling remote playback seems to have no effect on disabling
these events, and default media controls remote playback buttons still appear.

Add some utility methods to HTMLMediaElement to make it a bit cheaper to check whether
remote playback is disabled, and whether remote playback event listeners exist.

When changing the state of `disableRemotePlayback`, ensure that an event is fired saying
no remote playback targets exist, which cause media controls (including the native ones)
to hide the remote playback button.

* LayoutTests/media/airplay-target-availability-disableremoteplayback-expected.txt: Added.
* LayoutTests/media/airplay-target-availability-disableremoteplayback.html: Added.
* Source/WebCore/html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::~HTMLMediaElement):
(WebCore::HTMLMediaElement::attributeChanged):
(WebCore::HTMLMediaElement::setReadyState):
(WebCore::HTMLMediaElement::clearMediaPlayer):
(WebCore::HTMLMediaElement::wirelessRoutesAvailableDidChange):
(WebCore::HTMLMediaElement::enqueuePlaybackTargetAvailabilityChangedEvent):
(WebCore::HTMLMediaElement::remoteHasAvailabilityCallbacksChanged):
(WebCore::HTMLMediaElement::hasTargetAvailabilityListeners):
(WebCore::HTMLMediaElement::hasEnabledTargetAvailabilityListeners):
(WebCore::HTMLMediaElement::isWirelessPlaybackTargetDisabledChanged):
(WebCore::HTMLMediaElement::isWirelessPlaybackTargetDisabled const):
(WebCore::HTMLMediaElement::addEventListener):
(WebCore::HTMLMediaElement::removeEventListener):
* Source/WebCore/html/HTMLMediaElement.h:

https://github.com/WebKit/WebKit/commit/f958006ab842501cad67547605411074e64e1610

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	⏳ 🛠 wpe-skia
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash https://github.com/WebKit/WebKit/commit/aaa3495f953089021e9fb9ced2da58d7a7ba74f8)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
~~🧪 style~~	~~🛠 ios~~	~~🛠 mac~~	~~🛠 wpe~~	❌ 🛠 wincairo
~~🧪 bindings~~	~~🛠 ios-sim~~	~~🛠 mac-AS-debug~~	~~🧪 wpe-wk2~~
~~🧪 webkitperl~~	~~🧪 ios-wk2~~	~~🧪 api-mac~~	~~🧪 api-wpe~~
	~~🧪 ios-wk2-wpt~~	~~🧪 mac-wk1~~	⏳ 🛠 wpe-skia
	~~🧪 api-ios~~	~~🧪 mac-wk2~~	❌ 🛠 gtk
	❌ 🛠 tv	~~🧪 mac-AS-debug-wk2~~	❌ 🧪 gtk-wk2
	~~🛠 tv-sim~~	~~🧪 mac-wk2-stress~~	❌ 🧪 api-gtk
	❌ 🛠 watch
	~~🛠 watch-sim~~

[webkit-early-warning-system]

EWS run on previous version of this PR (hash https://github.com/WebKit/WebKit/commit/2001e77129bb1ec12c54cf78f4d9d484ef41144c)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	⏳ 🛠 wpe-skia
	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	❌ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 tv-sim	❌ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash https://github.com/WebKit/WebKit/commit/4d44a5bcd1e486199abfe436a4ff7517646fe54c)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	⏳ 🧪 wpe-wk2
✅ 🧪 webkitperl	~~🧪 ios-wk2~~	✅ 🧪 api-mac	✅ 🧪 api-wpe
	~~🧪 ios-wk2-wpt~~	❌ 🧪 mac-wk1	⏳ 🛠 wpe-skia
	⏳ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	~~🧪 mac-AS-debug-wk2~~	⏳ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	⏳ 🧪 api-gtk
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash https://github.com/WebKit/WebKit/commit/f958006ab842501cad67547605411074e64e1610)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	⏳ 🛠 wpe-skia
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash https://github.com/WebKit/WebKit/commit/0919d6df9c7c57ad18b6f2ae6a0ae035292d0016)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2
✅ 🧪 webkitperl	❌ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	✅ 🧪 mac-wk1	⏳ 🛠 wpe-skia
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	✅ 🛠 tv-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash https://github.com/WebKit/WebKit/commit/6e9854a8900f1bd757ecccf5125e06b49e1e1596)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 wincairo
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	~~🧪 wpe-wk2~~	~~🧪 wincairo-tests~~
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	~~🧪 api-mac~~	✅ 🧪 api-wpe
	~~🧪 ios-wk2-wpt~~	~~🧪 mac-wk1~~	✅ 🛠 wpe-cairo
	✅ 🧪 api-ios	~~🧪 mac-wk2~~	✅ 🛠 gtk
	✅ 🛠 tv	~~🧪 mac-AS-debug-wk2~~	~~🧪 gtk-wk2~~
	~~🛠 tv-sim~~	~~🧪 mac-wk2-stress~~	~~🧪 api-gtk~~
✅ 🛠 🧪 merge	~~🛠 watch~~
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 278933@main (7eb36e38f352): https://commits.webkit.org/278933@main

Reviewed commits have been landed. Closing PR #28599 and removing active labels.