Add experimental support for Portage 2.1.9.25.

sys-apps/portage/files/portage-2.1.9.25-fastbuild.patch

Index: sys-apps/portage/files/portage-2.1.9.25-fastbuild.patch
diff --git a/sys-apps/portage/files/portage-2.1.9.25-fastbuild.patch b/sys-apps/portage/files/portage-2.1.9.25-fastbuild.patch
new file mode 100644
index 0000000000000000000000000000000000000000..49bbe031db0018ecb805d39c1325e033370d918f
--- /dev/null
+++ b/sys-apps/portage/files/portage-2.1.9.25-fastbuild.patch
@@ -0,0 +1,26 @@
+--- a/pym/portage/dbapi/vartree.py.orig	2010-12-23 10:45:32.000000000 -0800
++++ b/pym/portage/dbapi/vartree.py	2010-12-23 11:30:58.000000000 -0800
+@@ -1293,14 +1293,15 @@
+ 			raise AssertionError("Lock already held.")
+ 		# At least the parent needs to exist for the lock file.
+ 		ensure_dirs(self.dbroot)
+-		if self._scheduler is None:
+-			self._lock_vdb = lockdir(self.dbroot)
+-		else:
+-			async_lock = AsynchronousLock(path=self.dbroot,
+-				scheduler=self._scheduler)
+-			async_lock.start()
+-			async_lock.wait()
+-			self._lock_vdb = async_lock
++		if os.environ.get("PORTAGE_LOCKS") != "false":
++			if self._scheduler is None:
++				self._lock_vdb = lockdir(self.dbroot)
++			else:
++				async_lock = AsynchronousLock(path=self.dbroot,
++					scheduler=self._scheduler)
++				async_lock.start()
++				async_lock.wait()
++				self._lock_vdb = async_lock
+ 
+ 	def unlockdb(self):
+ 		if self._lock_vdb is not None: