[GStreamer] ElementHarness: Remove custom sink query handler

[philn]

6c27891

[GStreamer] ElementHarness: Remove custom sink query handler
https://bugs.webkit.org/show_bug.cgi?id=251363

Reviewed by Xabier Rodriguez-Calvar.

In cases where the harnessed element reconfigures a source pad, the associated sink pad caps
need re-negotiation and it's better to let the default pad query handler do it.

* Source/WebCore/platform/gstreamer/GStreamerElementHarness.cpp:
(WebCore::GStreamerElementHarness::Stream::Stream):
(WebCore::GStreamerElementHarness::Stream::sinkQuery): Deleted.
* Source/WebCore/platform/gstreamer/GStreamerElementHarness.h:

Canonical link: https://commits.webkit.org/259619@main

4a510b7

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

[webkit-early-warning-system]

EWS run on current version of this PR (hash 4a510b7)

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

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 5dcec9f)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
⏳ 🧪 style	🛠 ios	⏳ 🛠 mac	⏳ 🛠 wpe	⏳ 🛠 🧪 win
⏳ 🧪 bindings	🛠 ios-sim	🛠 mac-AS-debug	⏳ 🛠 gtk	⏳ 🛠 wincairo
⏳ 🧪 webkitperl	🧪 ios-wk2	⏳ 🧪 api-mac	⏳ 🧪 gtk-wk2
⏳ 🧪 webkitpy	🧪 api-ios	⏳ 🧪 mac-wk1	⏳ 🧪 api-gtk
⏳ 🛠 🧪 jsc	⏳ 🛠 tv	⏳ 🧪 mac-wk2
	⏳ 🛠 tv-sim	🧪 mac-AS-debug-wk2
⏳ 🧪 services	⏳ 🛠 watch	⏳ 🧪 mac-wk2-stress
	⏳ 🛠 watch-sim

[webkit-commit-queue]

Committed 259619@main (6c27891): https://commits.webkit.org/259619@main

Reviewed commits have been landed. Closing PR #9319 and removing active labels.