Move remaining shared WebCore mac files to ../cocoa - #77276

c53e8b9

Move remaining shared WebCore mac files to ../cocoa
https://bugs.webkit.org/show_bug.cgi?id=327831
rdar://190224649

Reviewed by NOBODY (OOPS!).

Make it more self-evident which files are actually shared across ports.

All of these are compiled into the iOS build with code of their own, which
309708@main and related changes did not cover. This empties loader/mac and
history/mac.

SerializedPlatformDataCueMac becomes SerializedPlatformDataCueCocoa, and
FrameSelectionCocoa.mm guards its Mac-only part with PLATFORM(MAC) instead
of !PLATFORM(IOS_FAMILY). Addresses some of the style nits as well.

AudioSampleDataSource.mm drops an unused `using namespace JSC;`, which
leaked into SerializedPlatformDataCueCocoa.mm in the CMake build's larger
unified bundles and made JSValue ambiguous.

c53e8b9

Misc	iOS, visionOS, tvOS & watchOS	macOS	Linux	Windows	Apple Internal
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 win	⏳ 🛠 ios-apple
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🧪 wpe-wk2	⏳ 🧪 win-tests	⏳ 🛠 mac-apple
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	🧪 api-mac	✅ 🧪 api-wpe		⏳ 🛠 vision-apple
	✅ 🧪 ios-wk2-wpt	⏳ 🧪 api-mac-debug
	⏳ 🧪 api-ios	✅ 🧪 mac-wk2	✅ 🛠 gtk3-gcc
	⏳ 🛠 ios-safer-cpp	⏳ 🧪 mac-AS-debug-wk2	✅ 🛠 gtk
	✅ 🛠 vision		✅ 🧪 gtk-wk2
	✅ 🛠 vision-sim	⏳ 🧪 mac-intel-wk2	✅ 🧪 api-gtk
	✅ 🧪 vision-wk2	❌ 🛠 mac-safer-cpp	✅ 🛠 playstation
	✅ 🛠 tv	✅ 🧪 mac-site-isolation
	⏳ 🛠 tv-sim
	✅ 🛠 watch
	✅ 🛠 watch-sim