Fix misc compiler warnings, January 2023 edition

[mcatanzaro]

0b614af

Fix misc compiler warnings, January 2023 edition
https://bugs.webkit.org/show_bug.cgi?id=250945

Reviewed by Philippe Normand.

It's been a long time since my last round of warning fixes, since
warnings on EWS are fatal now, which is saving me a lot of effort. But
today I decided to try building with Clang instead of GCC, and it found
some problems that GCC misses.

* Source/JavaScriptCore/ftl/FTLOperations.cpp:
(JSC::FTL::JSC_DEFINE_JIT_OPERATION):
* Source/ThirdParty/xdgmime/CMakeLists.txt:
* Source/WebCore/page/scrolling/nicosia/ScrollingTreePositionedNodeNicosia.h:
* Source/WebCore/platform/audio/AudioUtilities.cpp:
(WebCore::AudioUtilities::timeToSampleFrame):
* Source/WebCore/platform/graphics/gstreamer/WebKitWebSourceGStreamer.cpp:
* Source/WebKit/UIProcess/API/gtk/WebKitWebViewBase.cpp:
(webkitWebViewBaseTakeViewSnapshot):
* Source/WebKit/UIProcess/gtk/ViewGestureControllerGtk.cpp:
(WebKit::ViewGestureController::beginSwipeGesture):
(WebKit::ViewGestureController::snapshot):
* Source/WebKit/WebProcess/InjectedBundle/API/glib/WebKitFrame.cpp:
(webkitFrameGetJSCValuesForElementsInWorld):
* Tools/TestWebKitAPI/Tests/WebKitGtk/TestContextMenu.cpp:

Canonical link: https://commits.webkit.org/259183@main

2c00ff3

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
❌ 🛠 🧪 jsc	✅ 🛠 tv	✅ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
✅ 🛠 🧪 merge	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[webkit-early-warning-system]

EWS run on current version of this PR (hash 2c00ff3)

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
❌ 🛠 🧪 jsc	✅ 🛠 tv	✅ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
✅ 🛠 🧪 merge	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[webkit-commit-queue]

Committed 259183@main (0b614af): https://commits.webkit.org/259183@main

Reviewed commits have been landed. Closing PR #8928 and removing active labels.