Split scm-specific functions out of gclient_scm.py to scm.py.

Reapplies r31809 is typo fixed.

TEST=unit tests fixed and reclassified
BUG=none

Review URL: http://codereview.chromium.org/393001

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@31812 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index dffc680..813f568 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -13,8 +13,10 @@
   'tests.gcl_unittest',
   'tests.gclient_test',
   'tests.gclient_scm_test',
+  'tests.gclient_utils_test',
   'tests.presubmit_unittest',
   'tests.revert_unittest',
+  'tests.scm_unittest',
   'tests.trychange_unittest',
   'tests.watchlists_unittest',
 ]