epiphany-app: Add support for running epiphany in application mode

This support is done configurable using the following variables:

EPIPHANY_APP             - Defines the app name (which needs to be the
			   directory name in FILESPATH/FILEEXTRAPATHS).
			   Currently defines it for HomeAssistant. If
			   this directory provides a
			   `service-override.conf`, the build system
			   will set it up as a systemd service
			   configuration for the main boot systemd
                           service.
EPIPHANY_URL             - The URL that the browser will load at
                           startup.
EPIPHANY_RDEPENDS        - Extra dependencies. If the specific
			   application needs extra dependencies at
                           runtime, they can be specifed here.
EPIPHANY_SERVICE_ENABLED - By default disabled (0). When enabled (1), it
			   will enable loading the epiphany app at boot.

The configuration defaults to setting up Epiphany browser in application
mode for a local instance of Home Assistant.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

meta-ohos-demo/recipes-gnome/epiphany/epiphany-app.bb

+SUMMARY = "Epiphany app mode support files"
+BUGTRACKER = "https://gitlab.gnome.org/GNOME/epiphany"
+LICENSE = "Apache-2.0"
+LIC_FILES_CHKSUM = "file://${OHOS_COREBASE}/LICENSES/Apache-2.0.txt;md5=ef3dabb8f39493f4ea410bebc1d01755"
+
+inherit allarch features_check
+
+EPIPHANY_APP ?= "HomeAssistant"
+EPIPHANY_URL ?= "http://localhost:8123"
+EPIPHANY_RDEPENDS ?= "python3-homeassistant"
+EPIPHANY_SERVICE_ENABLED ?= "0"
+
+# The services depend on weston
+REQUIRED_DISTRO_FEATURES = "wayland"
+
+SRC_URI = "\
+    file://epiphany-app@.service \
+    file://${EPIPHANY_APP}/* \
+    "
+
+do_install() {
+    # Setup the system service
+    install -d "${D}${systemd_unitdir}/system/multi-user.target.wants"
+    install -m 0644 "${WORKDIR}/epiphany-app@.service" "${D}${systemd_unitdir}/system"
+    sed -i -e 's,@EPIPHANY_APP@,${EPIPHANY_APP},g' \
+        -e 's,@EPIPHANY_URL@,${EPIPHANY_URL},g' "${D}${systemd_unitdir}/system/epiphany-app@.service"
+    if [ "${EPIPHANY_SERVICE_ENABLED}" = "1" ]; then
+        install -d "${D}${sysconfdir}/systemd/system/multi-user.target.wants"
+        ln -s "${systemd_unitdir}/system/epiphany-app@.service" \
+            "${D}${sysconfdir}/systemd/system/multi-user.target.wants/epiphany-app@${EPIPHANY_APP}.service"
+    fi
+
+    # The systemd service override is optional and app specific (for example it
+    # can add dependencies for a local HTTP service).
+    if [ -f "${WORKDIR}/epiphany-${EPIPHANY_APP}/service-override.conf" ]; then
+        mkdir -p "${D}${sysconfdir}/systemd/system/epiphany-app@${EPIPHANY_APP}.service.d"
+        cp "${WORKDIR}/epiphany-${EPIPHANY_APP}/service-override.conf" \
+            "${D}${sysconfdir}/systemd/system/epiphany-app@${EPIPHANY_APP}.service.d"
+    fi
+
+    # Setup the app
+    WD_APPDIR="${WORKDIR}/${EPIPHANY_APP}"
+    D_APPDIR="${D}/home/root/.local/share/epiphany-${EPIPHANY_APP}"
+    mkdir -p "$D_APPDIR"
+    cp "$WD_APPDIR/epiphany-${EPIPHANY_APP}.desktop" "$D_APPDIR"
+    touch "$D_APPDIR/.app"
+}
+
+FILES_${PN} += " \
+    /home/root \
+    ${systemd_unitdir} \
+    " 
+
+RDEPENDS_${PN} = "\
+    ${EPIPHANY_RDEPENDS} \
+    epiphany \
+    weston-init \
+    "

meta-ohos-demo/recipes-gnome/epiphany/epiphany-app/HomeAssistant/epiphany-HomeAssistant.desktop

+[Desktop Entry]
+Name=HomeAssistant
+Exec=epiphany --application-mode --profile="/home/root/.local/share/epiphany-HomeAssistant" http://localhost:8123
+StartupNotify=true
+Terminal=false
+Type=Application

meta-ohos-demo/recipes-gnome/epiphany/epiphany-app/HomeAssistant/service-override.conf

+[Unit]
+Requires=weston@root.service homeassistant.service
+After=weston@root.service homeassistant.service

meta-ohos-demo/recipes-gnome/epiphany/epiphany-app/epiphany-app@.service

+[Unit]
+Description=Epiphany browser started for %i application
+Requires=weston@root.service
+After=weston@root.service
+
+[Service]
+Environment="WAYLAND_DISPLAY=wayland-0"
+Environment="XDG_RUNTIME_DIR=/run/user/0"
+ExecStart=/usr/bin/epiphany -a --profile /home/root/.local/share/epiphany-@EPIPHANY_APP@ @EPIPHANY_URL@
+
+[Install]
+WantedBy=multi-user.target