chromium: Add chrome-virtual-keyboard recipe

chrome-virtual-keyboard is an extension to chromium that
has a javascript on-screen keyboard that allow users
to use chromium without a physical keyboard.

According to chrome webstore, there are over 700K users.

limitations:
    * upstream hasn't maintained this extension for a long time
    * not all textbox will work, notably iframes

leveraging the chromium flag:
--extension-load="" to load a local unpacked extension.

Signed-off-by: Yi Fan Yu <yifan.yu@windriver.com>

meta-chromium/classes/chromium-extension-package.bbclass

@@ -0,0 +1,2 @@
+# class for defining extension dir for chromium
+CHROMIUM_EXTENSION_DIR = "${datadir}/chromium/extensions"

meta-chromium/recipes-browser/chromium-extensions/chrome-virtual-keyboard_git.bb

@@ -0,0 +1,27 @@
+SUMMARY = "Chromium Virtual Keyboard"
+DESCRIPTION = "Virtual Keyboard Extension for Chromium/Chrome"
+HOMEPAGE = "https://apps.xontab.com/VirtualKeyboard"
+LICENSE = "MIT"
+LIC_FILES_CHKSUM = "file://LICENSE;md5=a8366463bacd4f2ec5edd419e8a113ff"
+
+SRC_URI = " \
+            git://github.com/xontab/${BPN}.git \
+"
+SRCREV = "e2b9adf4885cc4ed600cd9bccb77e0df8ff549aa"
+S = "${WORKDIR}/git"
+PV = "1.11.3+git${SRCPV}"
+
+inherit allarch chromium-extension-package
+
+do_compile[noexec] = "1"
+
+do_install() {
+    install -d ${D}${CHROMIUM_EXTENSION_DIR}/
+    cp -r ${S} ${D}${CHROMIUM_EXTENSION_DIR}/${BPN}
+
+    # remove unecessary artifacts
+    rm  -f ${D}${CHROMIUM_EXTENSION_DIR}/${BPN}/_config.yml
+    rm  -rf ${D}${CHROMIUM_EXTENSION_DIR}/${BPN}/.git/
+}
+
+FILES_${PN} += "${CHROMIUM_EXTENSION_DIR}/${BPN}"

meta-chromium/recipes-browser/chromium/chromium-gn.inc

@@ -2,7 +2,7 @@ require chromium.inc
 require chromium-unbundle.inc
 require gn-utils.inc
 
-inherit features_check gtk-icon-cache qemu
+inherit features_check gtk-icon-cache qemu chromium-extension-package
 
 # The actual directory name in out/ is irrelevant for GN.
 OUTPUT_DIR = "out/Release"
@@ -327,6 +327,7 @@ GN_ARGS:append:libc-musl = ' use_allocator_shim=false use_allocator="none"'
 CHROMIUM_EXTRA_ARGS ?= " \
         ${@bb.utils.contains('PACKAGECONFIG', 'use-egl', '--use-gl=egl', '', d)} \
         ${@bb.utils.contains('PACKAGECONFIG', 'kiosk-mode', '--kiosk --no-first-run --incognito', '', d)} \
+        --load-extension=\$(find ${CHROMIUM_EXTENSION_DIR} -maxdepth 1 | sed 1d | tr '\\\\n' , ) \
 "
 
 # V8's JIT infrastructure requires binaries such as mksnapshot and
@@ -443,7 +444,7 @@ do_install() {
 
 	# Add extra command line arguments to the chromium-wrapper script by
 	# modifying the dummy "CHROME_EXTRA_ARGS" line
-	sed -i "s/^CHROME_EXTRA_ARGS=\"\"/CHROME_EXTRA_ARGS=\"${CHROMIUM_EXTRA_ARGS}\"/" ${D}${libdir}/chromium/chromium-wrapper
+	sed -i "s#^CHROME_EXTRA_ARGS=\"\"#CHROME_EXTRA_ARGS=\"${CHROMIUM_EXTRA_ARGS}\"#" ${D}${libdir}/chromium/chromium-wrapper
 
 	# This is ANGLE, not to be confused with the similarly named files under swiftshader/
 	if [ -e libEGL.so ]; then