[iOS] Improve support for <input type="file" webkitdirectory>

[lilyspiniolas]

ca350c2

[iOS] Improve support for <input type="file" webkitdirectory>
https://bugs.webkit.org/show_bug.cgi?id=271705
rdar://125457578

Reviewed by Wenson Hsieh.

WKFileUploadPanel now checks for the webkitdirectory attribute, and if present
sets the mode of the UIDocumentPickerViewController to the required
UIDocumentPickerModeOpen rather than UIDocumentPickerModeImport. The contents
of selected directories are then manually imported in order to be uploaded.

* Source/WebKit/UIProcess/ios/forms/WKFileUploadPanel.mm:
(-[WKFileUploadPanel presentWithParameters:resultListener:]):

Canonical link: https://commits.webkit.org/284685@main

1360f93

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt		✅ 🛠 wpe-cairo
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2
	✅ 🛠 tv	✅ 🛠 mac-safer-cpp
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 7a579aa)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
❌ 🧪 style	❌ 🛠 ios	❌ 🛠 mac	❌ 🛠 wpe	❌ 🛠 win
	❌ 🛠 ios-sim	❌ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2	❌ 🧪 win-tests
❌ 🧪 webkitperl	❌ 🧪 ios-wk2	❌ 🧪 api-mac	❌ 🧪 api-wpe
	❌ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	❌ 🛠 wpe-cairo
	❌ 🧪 api-ios	❌ 🧪 mac-wk2	❌ 🛠 gtk
	❌ 🛠 vision	❌ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	❌ 🛠 vision-sim	❌ 🧪 mac-wk2-stress	❌ 🧪 api-gtk
	⏳ 🧪 vision-wk2	❌ 🧪 mac-intel-wk2
	❌ 🛠 tv	🛠 mac-safer-cpp
	❌ 🛠 tv-sim
	❌ 🛠 watch
	❌ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash af17f57)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
❌ 🧪 style	❌ 🛠 ios	❌ 🛠 mac	❌ 🛠 wpe	❌ 🛠 win
	❌ 🛠 ios-sim	❌ 🛠 mac-AS-debug	❌ 🧪 wpe-wk2	❌ 🧪 win-tests
❌ 🧪 webkitperl	❌ 🧪 ios-wk2	❌ 🧪 api-mac	❌ 🧪 api-wpe
🧪 webkitpy	❌ 🧪 ios-wk2-wpt	❌ 🧪 mac-wk1	❌ 🛠 wpe-cairo
	❌ 🧪 api-ios	❌ 🧪 mac-wk2	❌ 🛠 gtk
	❌ 🛠 vision	❌ 🧪 mac-AS-debug-wk2	❌ 🧪 gtk-wk2
	❌ 🛠 vision-sim	❌ 🧪 mac-wk2-stress	❌ 🧪 api-gtk
	⏳ 🧪 vision-wk2	❌ 🧪 mac-intel-wk2	🛠 jsc-armv7
	❌ 🛠 tv	🛠 mac-safer-cpp	🧪 jsc-armv7-tests
	❌ 🛠 tv-sim
	❌ 🛠 watch
	❌ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on previous version of this PR (hash f9fe5a2)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt		✅ 🛠 wpe-cairo
	🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2
	✅ 🛠 tv	🛠 mac-safer-cpp
	✅ 🛠 tv-sim
	❌ 🛠 watch
	❌ 🛠 watch-sim

[webkit-early-warning-system]

EWS run on current version of this PR (hash 1360f93)

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win
	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	✅ 🧪 win-tests
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 api-wpe
	✅ 🧪 ios-wk2-wpt		✅ 🛠 wpe-cairo
	✅ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk
	✅ 🛠 vision	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	✅ 🧪 mac-wk2-stress	✅ 🧪 api-gtk
✅ 🛠 🧪 merge	✅ 🧪 vision-wk2	✅ 🧪 mac-intel-wk2
	✅ 🛠 tv	✅ 🛠 mac-safer-cpp
	✅ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim

[webkit-commit-queue]

Committed 284685@main (ca350c2): https://commits.webkit.org/284685@main

Reviewed commits have been landed. Closing PR #34675 and removing active labels.