feat(sys-apps/portage): Adding repos.conf patch to ebuild

Pulling in the patch mentioned here
(https://bugs.gentoo.org/show_bug.cgi?id=507284). This adds support for the
'disabled' attribute in repository sections within repos.conf.

sdk_container/src/third_party/coreos-overlay/sys-apps/portage/files/portage-2.2.8-add-disabled.patch

@@ -0,0 +1,47 @@
+commit b2f0e82190e7343374f399d7b0246587ee945870
+Author: Alex Crawford <alex.crawford@coreos.com>
+Date:   Mon Apr 14 12:43:56 2014 -0700
+
+    Adding disabled attribute to repos.conf
+    
+    This flag allows a repos.conf file to disable a previously-defined repository.
+
+diff --git a/pym/portage/repository/config.py b/pym/portage/repository/config.py
+index 5e0d055..b8b3180 100644
+--- a/pym/portage/repository/config.py
++++ b/pym/portage/repository/config.py
+@@ -78,8 +78,8 @@ class RepoConfig(object):
+ 	"""Stores config of one repository"""
+ 
+ 	__slots__ = ('aliases', 'allow_missing_manifest', 'allow_provide_virtual',
+-		'cache_formats', 'create_manifest', 'disable_manifest', 'eapi',
+-		'eclass_db', 'eclass_locations', 'eclass_overrides',
++		'cache_formats', 'create_manifest', 'disabled', 'disable_manifest',
++		'eapi', 'eclass_db', 'eclass_locations', 'eclass_overrides',
+ 		'find_invalid_path_char', 'force', 'format', 'local_config', 'location',
+ 		'main_repo', 'manifest_hashes', 'masters', 'missing_repo_name',
+ 		'name', 'portage1_profiles', 'portage1_profiles_compat', 'priority',
+@@ -173,6 +173,11 @@ class RepoConfig(object):
+ 			location = None
+ 		self.location = location
+ 
++		disabled = repo_opts.get('disabled')
++		if disabled is not None:
++			disabled = disabled.strip().lower() == 'true'
++		self.disabled = disabled or False
++
+ 		eapi = None
+ 		missing = True
+ 		self.name = name
+@@ -633,7 +638,10 @@ class RepoConfigLoader(object):
+ 		# Do this before expanding aliases, so that location_map and
+ 		# treemap consistently map unaliased names whenever available.
+ 		for repo_name, repo in list(prepos.items()):
+-			if repo.location is None:
++			if repo.disabled:
++				del prepos[repo_name]
++				continue
++			elif repo.location is None:
+ 				if repo_name != 'DEFAULT':
+ 					# Skip this warning for repoman (bug #474578).
+ 					if settings.local_config and paths:

sdk_container/src/third_party/coreos-overlay/sys-apps/portage/portage-2.2.8-r2.ebuild

@@ -228,6 +228,7 @@ src_prepare() {
 		fi
 		epatch "${WORKDIR}/${PN}-${PATCHVER}.patch"
 	fi
+	epatch "${FILESDIR}/${P}-add-disabled.patch"
 	einfo "Setting portage.VERSION to ${PVR} ..."
 	sed -e "s/^VERSION=.*/VERSION=\"${PVR}\"/" -i pym/portage/__init__.py || \
 		die "Failed to patch portage.VERSION"