Fix webkitpy scm_unittests so that they pass again.

Tools/Scripts/webkitpy/common/checkout/scm/svn.py

Index: Tools/Scripts/webkitpy/common/checkout/scm/svn.py
diff --git a/Tools/Scripts/webkitpy/common/checkout/scm/svn.py b/Tools/Scripts/webkitpy/common/checkout/scm/svn.py
index 54f2fa8e750a76a46de89801ae281ce08c947191..4236d0931b5fbe34dcf6782ee2d1ee291bc27305 100644
--- a/Tools/Scripts/webkitpy/common/checkout/scm/svn.py
+++ b/Tools/Scripts/webkitpy/common/checkout/scm/svn.py
@@ -120,16 +120,21 @@ class SVN(SCM):
         field_count = 6 if self._svn_version() > "1.6" else 5
         return "^(?P<status>[%s]).{%s} (?P<filename>.+)$" % (expected_types, field_count)
 
-    def _add_parent_directories(self, path):
+    def _add_parent_directories(self, path, recurse):
         """Does 'svn add' to the path and its parents."""
         if self.in_working_directory(path):
             return
-        self.add(path)
+        self.add(path, recurse=recurse)
 
-    def add_list(self, paths, return_exit_code=False):
+    def add_list(self, paths, return_exit_code=False, recurse=True):
         for path in paths:
-            self._add_parent_directories(os.path.dirname(os.path.abspath(path)))
-        return self._run_svn(["add"] + paths, return_exit_code=return_exit_code)
+            self._add_parent_directories(os.path.dirname(os.path.abspath(path)),
+                                         recurse=False)
+        if recurse:
+            cmd = ["add"] + paths
+        else:
+            cmd = ["add", "--depth", "empty"] + paths
+        return self._run_svn(cmd, return_exit_code=return_exit_code)
 
     def _delete_parent_directories(self, path):
         if not self.in_working_directory(path):