Optional chroot when installing nodejs

src/freedombone-utils-nodejs

 }
 
 function mesh_install_nodejs {
-    chroot "$rootdir" apt-get -yq install g++ m4 libtool automake nodejs curl
-    chroot "$rootdir" apt-get -yq install libxext-dev libxtst-dev libxkbfile-dev
+    mesh_install_nodejs_prefix=
+    if [ $rootdir ]; then
+        mesh_install_nodejs_prefix="chroot $rootdir"
+    fi
+    $mesh_install_nodejs_prefix apt-get -yq install g++ m4 libtool automake nodejs curl
+    $mesh_install_nodejs_prefix apt-get -yq install libxext-dev libxtst-dev libxkbfile-dev
 
     if [ ! -f ${rootdir}/usr/bin/nodejs ]; then
         echo $'nodejs was not installed'
         echo $'Unable to download npm installer'
         exit 8793636
     fi
-    chroot "$rootdir" chmod +x /root/npm_install.sh
+    $mesh_install_nodejs_prefix chmod +x /root/npm_install.sh
     sed -i "s|t=\"\${npm_install}\"|t=\"$NPM_VERSION\"|g" $rootdir/root/npm_install.sh
-    chroot "$rootdir" /root/npm_install.sh
+    $mesh_install_nodejs_prefix /root/npm_install.sh
 
     if [ ! -f $rootdir/usr/bin/npm ]; then
         echo $'npm was not installed'
 
     # update from the old debian nodejs version
     get_npm_arch
-    chroot "$rootdir" npm install --arch=$NPM_ARCH -g n@${NODEJS_N_VERSION} --save
-    chroot "$rootdir" n --arch $N_ARCH ${NODEJS_VERSION}
+    $mesh_install_nodejs_prefix npm install --arch=$NPM_ARCH -g n@${NODEJS_N_VERSION} --save
+    $mesh_install_nodejs_prefix n --arch $N_ARCH ${NODEJS_VERSION}
     cp $rootdir/root/npm $rootdir/usr/bin/npm
 }