fix(qtdeclarative): properly generate qtquick-config.h features

The qtquick-config.h file was being generated empty by the cmake
build, causing 'division by zero in #if' errors in downstream
consumers (SDDM, KWin) because QT_CONFIG(quick_shadereffect) and
QT_CONFIG(quick_draganddrop) were undefined.

Two fixes:
1. Explicitly enable QT_FEATURE_quick_shadereffect and
   QT_FEATURE_quick_draganddrop in the cmake configuration.
2. Add a safety net that regenerates qtquick-config.h with the
   required feature definitions if cmake produces an empty file.

local/recipes/libs/libepoxy/source/.github/scripts/epoxy-ci-linux.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+
+dump_log_and_quit() {
+        local exitcode=$1
+
+        cat meson-logs/testlog.txt
+
+        exit $exitcode
+}
+
+# Start Xvfb
+XVFB_WHD=${XVFB_WHD:-1280x720x16}
+
+Xvfb :99 -ac -screen 0 $XVFB_WHD -nolisten tcp &
+xvfb=$!
+
+export DISPLAY=:99
+
+srcdir=$( pwd )
+builddir=$( mktemp -d build_XXXXXX )
+
+meson --prefix /usr "$@" $builddir $srcdir || exit $?
+
+cd $builddir
+
+ninja || exit $?
+meson test || dump_log_and_quit $?
+
+cd ..
+
+# Stop Xvfb
+kill -9 ${xvfb}

local/recipes/libs/libepoxy/source/.github/scripts/epoxy-ci-osx.sh

@@ -0,0 +1,27 @@
+#!/bin/sh
+
+dump_log_and_quit() {
+        local exitcode=$1
+
+        cat meson-logs/testlog.txt
+
+        exit $exitcode
+}
+
+export SDKROOT=$( xcodebuild -version -sdk macosx Path )
+export CPPFLAGS=-I/usr/local/include
+export LDFLAGS=-L/usr/local/lib
+export OBJC=$CC
+export PATH=$HOME/tools:$PATH
+
+srcdir=$( pwd )
+builddir=$( mktemp -d build_XXXXXX )
+
+meson ${BUILDOPTS} $builddir $srcdir || exit $?
+
+cd $builddir
+
+ninja || exit $?
+meson test || dump_log_and_quit $?
+
+cd ..