Add dev-qt from an older version of the gentoo repo

Qt5 has been removed, we restore it since we still use it.

dev-qt/qttest/Manifest

@@ -0,0 +1,5 @@
+DIST qtbase-5.15-gentoo-patchset-6.tar.xz 8288 BLAKE2B ad9695a528345dd3b8e9ce72b7bdfe8f744f16685a567bbc7862ba6c28e5a426260cb0b73e2573cb3a6f16f1785786898ffb44c90f5d75354b97e5756c7573db SHA512 97bc4d5375e1750a5578439ff320ee2e5e929df1dafe56b4e86f2de8ad26c91dc4002e45ad75d9f936347d49b9f54c0c42f8fc2cb7dfd4f54bf08a210b3bc720
+DIST qtbase-5.15.18-gentoo-kde-1.tar.xz 450532 BLAKE2B 172732fe6a2f7dd4718b224d8a8ba7b182ded24f74ee38545d20a17364757153b399cae82b40f425e72b2587ec432f024868078edfe95280242211a040ddd9f6 SHA512 e0257171cf723cb6208a06f28fc95fa07d1239ea9dd3daa79d362146aa53e008398c9e1d95443b84d6d71b835a3f010b957e748f3ec23b77a588d6b372fd0c47
+DIST qtbase-everywhere-opensource-src-5.15.18.tar.xz 51492796 BLAKE2B a02f13f2ae8d3994fe5e3fa5b3751cb2981c3203cc4f3859dd4398d6a62101772885acb0c7b1f830ba8e9fbdd64ecfdb2a6074bfedd1bd372b4fc9ceb747467d SHA512 d39c831e6f3ddcd6a50f103ff60a0700b451f137782249508b7447a80066e3e9259c9b5038e6077ccf8df06b6afefec232c3c4dd331d85765089c92571708206
+EBUILD qttest-5.15.18.ebuild 568 BLAKE2B b874576e281b5c6b42421078b76903587c51cd9ceaa0e7d3baf2017f608cc8d75ffe4e9c427e7c4b71c92912ab4f18b8995985ecef61c310a82fc070350c2779 SHA512 50b2d7cd13409edcb2b15c19a92a70e3ff9e8ccc873100585dfdf5d544fd0496b1938f8cb098ffe36ac4263c868fbfaf56b362ab447a001d10d0bd2f204d805b
+MISC metadata.xml 482 BLAKE2B 651a49dc4a07f5e5a9c21990868e666d98acdea7d7b0b2c0e4c98eafc3da72c803d380e4abda30f33250f7bbd7654df713833ccdddcb975cbad6f92e488f643b SHA512 192c670abd7da29645513bf1d9297d942efdc49f5cf170861e7689fda47f51daa47f10c7c81c3b045366e0259179c6839ff7747197c9d792e8d0fd1a5818973e

dev-qt/qttest/metadata.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE pkgmetadata SYSTEM "https://www.gentoo.org/dtd/metadata.dtd">
+<pkgmetadata>
+	<maintainer type="project">
+		<email>qt@gentoo.org</email>
+		<name>Gentoo Qt Project</name>
+	</maintainer>
+	<upstream>
+		<bugs-to>https://bugreports.qt.io/</bugs-to>
+		<doc>https://doc.qt.io/</doc>
+	</upstream>
+	<slots>
+		<subslots>
+			Must only be used by packages that are known to use private parts of the Qt API.
+		</subslots>
+	</slots>
+</pkgmetadata>

dev-qt/qttest/qttest-5.15.18.ebuild

@@ -0,0 +1,33 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+if [[ ${PV} != *9999* ]]; then
+	QT5_KDEPATCHSET_REV=1
+	KEYWORDS="amd64 arm arm64 ~hppa ~loong ppc ppc64 ~riscv x86"
+fi
+
+QT5_MODULE="qtbase"
+VIRTUALX_REQUIRED="test"
+inherit qt5-build
+
+DESCRIPTION="Unit testing library for the Qt5 framework"
+
+IUSE=""
+
+RDEPEND="=dev-qt/qtcore-${QT5_PV}*:5="
+DEPEND="${RDEPEND}
+	test? (
+		=dev-qt/qtgui-${QT5_PV}*
+		=dev-qt/qtxml-${QT5_PV}*
+	)
+"
+
+QT5_TARGET_SUBDIRS=(
+	src/testlib
+)
+
+QT5_GENTOO_PRIVATE_CONFIG=(
+	:testlib
+)