Prepare vboot_reference ebuild to work with the new makefile and build flow.

chromeos-base/vboot_reference/vboot_reference-1.0.ebuild

 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Distributed under the terms of the GNU General Public License v2
 
-inherit eutils toolchain-funcs git
+inherit cros-workon
 
 DESCRIPTION="Chrome OS verified boot tools"
 LICENSE="GPL-3"
 SLOT="0"
-KEYWORDS="amd64 x86 arm"
+KEYWORDS="amd64 arm x86"
 IUSE="minimal"
 EAPI="2"
 
 DEPEND="dev-libs/openssl
         sys-apps/util-linux"
 
 EGIT_REPO_URI=git://chromiumos-git/git/repos/not-yet-populated.git
 SRCPATH=src/platform/vboot_reference
 
-src_unpack() {
-        if [ -z "${CHROMEOS_ROOT}" ] ; then
-                local CHROMEOS_ROOT=$(eval echo -n ~${SUDO_USER}/trunk)
-        fi
-        if [ -e "${CHROMEOS_ROOT}/${SRCPATH}" ] ; then
-                cp -a "${CHROMEOS_ROOT}/${SRCPATH}" "${S}" || die
-        else
-                git_src_unpack
-        fi
-}
-
-
 src_compile() {
         tc-export CC AR CXX
-        emake || die "${SRCPATH} compile failed."
+        err_msg="${SRCPATH} compile failed. "
+        err_msg+="Try running 'make clean' in the package root directory"
+        emake || die "${err_msg}"
 }
 
 src_install() {
         if use minimal ; then
-                emake DESTDIR="${D}/usr/bin" -C cgpt install || \
-                        die "${SRCPATH} install failed."
-        else                 
+                emake DESTDIR="${D}/usr/bin" BUILD="${S}"/build -C cgpt \
+                      install || die "${SRCPATH} install failed."
+        else
                 emake DESTDIR="${D}/usr/bin" install || \
                         die "${SRCPATH} install failed."
         fi
 }