Make release scripts even more robust.

tools/release/test_scripts.py

 #!/usr/bin/env python
 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
@@ skipping 1388 matching lines @@
       Cmd("git log -1 --format=%H hash_456^", "master_456"),
       Cmd("git log -1 --format=%B master_456",
           "Cr-Commit-Position: refs/heads/master@{#456}"),
       Cmd("git log -1 --format=%B hash_456", c_hash_456_commit_log),
       Cmd("git log -1 --format=%ci hash_456", "02:15"),
       Cmd("git checkout -f HEAD -- %s" % VERSION_FILE, "",
           cb=ResetVersion(3, 22, 5)),
       Cmd("git status -s -uno", "", cwd=chrome_dir),
       Cmd("git checkout -f master", "", cwd=chrome_dir),
       Cmd("git pull", "", cwd=chrome_dir),
+      Cmd("git branch", "  branch1\n* %s" % TEST_CONFIG["BRANCHNAME"],
+          cwd=chrome_dir),
+      Cmd("git branch -D %s" % TEST_CONFIG["BRANCHNAME"], "",
+          cwd=chrome_dir),
       Cmd("git new-branch %s" % TEST_CONFIG["BRANCHNAME"], "",
           cwd=chrome_dir),
       Cmd("git fetch origin", "", cwd=chrome_v8_dir),
       Cmd("git log --format=%H --grep=\"V8\"",
           "c_hash0\nc_hash1\nc_hash2\nc_hash3\n",
           cwd=chrome_dir),
       Cmd("git diff --name-only c_hash0 c_hash0^", "", cwd=chrome_dir),
       Cmd("git diff --name-only c_hash1 c_hash1^", "DEPS", cwd=chrome_dir),
       Cmd("git checkout -f c_hash1 -- DEPS", "",
           cb=ResetDEPS("hash_456"),
@@ skipping 117 matching lines @@
 
 Review URL: https://codereview.chromium.org/83173002
 
 ------------------------------------------------------------------------""")
     self.assertEquals(
 """Prepare push to trunk.  Now working on version 3.23.11.
 
 R=danno@chromium.org
 
 Committed: https://code.google.com/p/v8/source/detail?r=17997""", body)