[iOS] Stop using AVSystemController and AVAudioSession SPIs when media capability grants are enabled

[aestes]

f0f4cef

[iOS] Stop using AVSystemController and AVAudioSession SPIs when media capability grants are enabled
https://bugs.webkit.org/show_bug.cgi?id=266975
rdar://115750175

Reviewed by Per Arne Vollan.

When media capability grants are enabled, setting the
AVSystemController_PIDToInheritApplicationStateFrom attribute on AVSystemController and calling
-[AVAudioSession setAuditTokensForProcessAssertion:error:] are no longer necessary. Plumbed the
MediaCapabilityGrantsEnabled web preference to the GPU process and avoided calling these SPIs when
the preference is activated. Added a WKPreferences SPI to deactivate the preference for use by
clients that are not yet ready to adopt media capability grants.

* Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml:
* Source/WebCore/platform/audio/PlatformMediaSessionManager.cpp:
(WebCore::PlatformMediaSessionManager::mediaCapabilityGrantsEnabled):
(WebCore::PlatformMediaSessionManager::setMediaCapabilityGrantsEnabled):
* Source/WebCore/platform/audio/PlatformMediaSessionManager.h:
* Source/WebCore/platform/audio/ios/MediaSessionHelperIOS.mm:
(MediaSessionHelperIOS::providePresentingApplicationPID):
* Source/WebKit/GPUProcess/GPUProcess.cpp:
(WebKit::GPUProcess::updateGPUProcessPreferences):
* Source/WebKit/GPUProcess/GPUProcessPreferences.cpp:
(WebKit::GPUProcessPreferences::copyEnabledWebPreferences):
* Source/WebKit/GPUProcess/GPUProcessPreferences.h:
* Source/WebKit/GPUProcess/media/RemoteAudioSessionProxyManager.cpp:
(WebKit::RemoteAudioSessionProxyManager::updatePresentingProcesses):
* Source/WebKit/UIProcess/API/Cocoa/WKPreferences.mm:
(-[WKPreferences _mediaCapabilityGrantsEnabled]):
(-[WKPreferences _setMediaCapabilityGrantsEnabled:]):
* Source/WebKit/UIProcess/API/Cocoa/WKPreferencesPrivate.h:

Canonical link: https://commits.webkit.org/272675@main

65bfe58

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	✅ 🛠 gtk
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🧪 gtk-wk2
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv-sim		✅ 🛠 jsc-armv7
✅ 🛠 🧪 merge	✅ 🛠 watch		✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 65bfe58)

Details

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	✅ 🛠 gtk
✅ 🛠 🧪 jsc	✅ 🧪 api-ios	❌ 🧪 mac-wk2	✅ 🧪 gtk-wk2
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 api-gtk
	✅ 🛠 tv-sim		✅ 🛠 jsc-armv7
✅ 🛠 🧪 merge	✅ 🛠 watch		✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch-sim

[aestes]

Test failure in tiled-drawing/scrolling/scroll-snap/scroll-snap-mandatory-mainframe-vertical-then-horizontal.html is unrelated

[pvollan]

R=me.

[webkit-commit-queue]

Committed 272675@main (f0f4cef): https://commits.webkit.org/272675@main

Reviewed commits have been landed. Closing PR #22293 and removing active labels.