Add coverage analysis to push and merge script tests.

tools/push-to-trunk/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 220 matching lines @@
 
 class SimpleMock(object):
   def __init__(self, name):
     self._name = name
     self._recipe = []
     self._index = -1
 
   def Expect(self, recipe):
     self._recipe = recipe
 
-  def Call(self, *args):
+  def Call(self, *args):  # pragma: no cover
     self._index += 1
     try:
       expected_call = self._recipe[self._index]
     except IndexError:
       raise NoRetryException("Calling %s %s" % (self._name, " ".join(args)))
 
     # Pack expectations without arguments into a list.
     if not isinstance(expected_call, list):
       expected_call = [expected_call]
 
@@ skipping 17 matching lines @@
       except:
         tb = traceback.format_exc()
         raise NoRetryException("Caught exception from callback: %s" % tb)
     return_value = expected_call[len(args)]
 
     # If the return value is an exception, raise it instead of returning.
     if isinstance(return_value, Exception):
       raise return_value
     return return_value
 
-  def AssertFinished(self):
+  def AssertFinished(self):  # pragma: no cover
     if self._index < len(self._recipe) -1:
       raise NoRetryException("Called %s too seldom: %d vs. %d"
                              % (self._name, self._index, len(self._recipe)))
 
 
 class ScriptTest(unittest.TestCase):
   def MakeEmptyTempFile(self):
     handle, name = tempfile.mkstemp()
     os.close(handle)
     self._tmp_files.append(name)
@@ skipping 721 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)