Fix more pylint warnings.

BUG=none
TEST=Trybot runs, pylint.

Change-Id: Ic5b4b9759e29842509816e59d9c286b1bd09d10c
Reviewed-on: https://gerrit.chromium.org/gerrit/39786
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Ready: David James <davidjames@chromium.org>
Tested-by: David James <davidjames@chromium.org>
diff --git a/scripts/cros_extract_deps.py b/scripts/cros_extract_deps.py
index 32f345a..512f7db 100644
--- a/scripts/cros_extract_deps.py
+++ b/scripts/cros_extract_deps.py
@@ -8,7 +8,7 @@
 import sys
 from parallel_emerge import DepGraphGenerator
 
-def FlattenDepTree(deptree, pkgtable={}, parentcpv=None):
+def FlattenDepTree(deptree, pkgtable=None, parentcpv=None):
   """
   Turn something like this (the parallel_emerge DepsTree format):
 {
@@ -46,9 +46,11 @@
   }
 }
   """
+  if pkgtable is None:
+    pkgtable = {}
   for cpv, record in deptree.items():
     if cpv not in pkgtable:
-      cat, nam, ver, rev = portage.catpkgsplit(cpv)
+      cat, nam, ver, rev = portage.versions.catpkgsplit(cpv)
       pkgtable[cpv] = {"deps": [],
                        "rev_deps": [],
                        "name": nam,
@@ -101,5 +103,5 @@
 
   deps = DepGraphGenerator()
   deps.Initialize(argv)
-  deps_tree, deps_info = deps.GenDependencyTree()
+  deps_tree, _deps_info = deps.GenDependencyTree()
   print json.dumps(FlattenDepTree(deps_tree), sort_keys=True, indent=2)