Fix many (but not all[1]) depot_tools tests on Windows.

[1] *scm_test.py are deeply broken, svnadmin is missing for svn_bin\.
And the git test are failing at shutdown.

Also Fix SvnCheckout.testMove flakiness.

TBR=ilevy@chromium.org,szager@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/14729012

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@198900 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/tests/gclient_scm_test.py b/tests/gclient_scm_test.py
index 3640a3e..3f1ff3b 100755
--- a/tests/gclient_scm_test.py
+++ b/tests/gclient_scm_test.py
@@ -1064,7 +1064,7 @@
     self.fake_hash_1 = 't0ta11yf4k3'
     self.fake_hash_2 = '3v3nf4k3r'
     self.url = 'git://foo'
-    self.root_dir = '/tmp'
+    self.root_dir = '/tmp' if sys.platform != 'win32' else 't:\\tmp'
     self.relpath = 'fake'
     self.base_path = os.path.join(self.root_dir, self.relpath)