Remove SVN support from apply_issue

R=iannucci@chromium.org
BUG=475320

Review-Url: https://codereview.chromium.org/2394963003

apply_issue.py

@@ -263,9 +263,7 @@ def main():
         patch.patchlevel += options.extra_patchlevel
     full_dir = os.path.abspath(options.root_dir)
     scm_type = scm.determine_scm(full_dir)
-    if scm_type == 'svn':
-      scm_obj = checkout.SvnCheckout(full_dir, None, None, None, None)
-    elif scm_type == 'git':
+    if scm_type == 'git':
       scm_obj = checkout.GitCheckout(full_dir, None, None, None, None)
     elif scm_type == None:
       scm_obj = checkout.RawCheckout(full_dir, None, None)
@@ -306,8 +304,6 @@ def main():
             '--nohooks',
             '--delete_unversioned_trees',
             ]
-        if scm_type == 'svn':
-          cmd.extend(['--revision', 'BASE'])
         if options.revision_mapping:
           cmd.extend(['--output-json', f])