Fix error messages

testing_support/coverage_utils.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import distutils.version
 import os
 import sys
 import textwrap
 import unittest
 
 ROOT_PATH = os.path.abspath(os.path.join(
     os.path.dirname(os.path.dirname(__file__))))
 
 
 def native_error(msg, version):
   print textwrap.dedent("""\
   ERROR: Native python-coverage (version: %s) is required to be
   installed on your PYTHONPATH to run this test. Recommendation:
-     sudo pip install python-coverage
+     sudo apt-get install pip
+     sudo pip install --upgrade coverage
   %s""") % (version, msg)
   sys.exit(1)
 
 def covered_main(includes, require_native=None):
   """Equivalent of unittest.main(), except that it gathers coverage data, and
   asserts if the test is not at 100% coverage.
 
   Args:
     includes (list(str) or str) - List of paths to include in coverage report.
       May also be a single path instead of a list.
     require_native (str) - If non-None, will require that
       at least |require_native| version of coverage is installed on the
       system with CTracer.
   """
   try:
     import coverage
     if require_native is not None:
       got_ver = coverage.__version__
-      if not coverage.collector.CTracer:
+      if not getattr(coverage.collector, 'CTracer', None):
         native_error((
             "Native python-coverage module required.\n"
             "Pure-python implementation (version: %s) found: %s"
           ) % (got_ver, coverage), require_native)
       if got_ver < distutils.version.LooseVersion(require_native):
         native_error("Wrong version (%s) found: %s" % (got_ver, coverage),
                      require_native)
   except ImportError:
     if require_native is None:
       sys.path.insert(0, os.path.join(ROOT_PATH, 'third_party'))
@@ skipping 11 matching lines @@
     unittest.main()
   except SystemExit as e:
     retcode = e.code or retcode
 
   COVERAGE.stop()
   if COVERAGE.report() != 100.0:
     print 'FATAL: not at 100% coverage.'
     retcode = 2
 
   return retcode