Bug 1866829 - Replace obsolete distutils reference by portable alternatives r=ahochheiden

distutils.dir_util.copy_tree -> shutil.copytree
distutils.spawn.find_executable -> shutil.which

Also fix a warning about escape sequence in the process.

Differential Revision: https://phabricator.services.mozilla.com/D194781

diff --git a/testing/mozbase/mozdevice/mozdevice/adb.py b/testing/mozbase/mozdevice/mozdevice/adb.py
--- a/testing/mozbase/mozdevice/mozdevice/adb.py
+++ b/testing/mozbase/mozdevice/mozdevice/adb.py
@@ -10,17 +10,17 @@ import re
 import shlex
 import shutil
 import signal
 import subprocess
 import sys
 import tempfile
 import time
 import traceback
-from distutils import dir_util
+from shutil import copytree
 from threading import Thread
 
 import six
 from six.moves import range
 
 from . import version_codes
 
 _TEST_ROOT = None
@@ -2978,17 +2978,17 @@ class ADBDevice(ADBCommand):
         if os.path.isfile(local) and self.is_dir(remote):
             # force push to use the correct filename in the remote directory
             remote = posixpath.join(remote, os.path.basename(local))
         elif os.path.isdir(local):
             copy_required = True
             temp_parent = tempfile.mkdtemp()
             remote_name = os.path.basename(remote)
             new_local = os.path.join(temp_parent, remote_name)
-            dir_util.copy_tree(local, new_local)
+            copytree(local, new_local)
             local = new_local
             # See do_sync_push in
             # https://android.googlesource.com/platform/system/core/+/master/adb/file_sync_client.cpp
             # Work around change in behavior in adb 1.0.36 where if
             # the remote destination directory exists, adb push will
             # copy the source directory *into* the destination
             # directory otherwise it will copy the source directory
             # *onto* the destination directory.
@@ -3131,17 +3131,17 @@ class ADBDevice(ADBCommand):
                     self.cp(remote, intermediate, recursive=True, timeout=timeout)
                     self.command_output(["pull", intermediate, local], timeout=timeout)
                 except ADBError as e:
                     self._logger.error("pull %s %s: %s" % (intermediate, local, str(e)))
                 finally:
                     self.rm(intermediate, recursive=True, force=True, timeout=timeout)
         finally:
             if copy_required:
-                dir_util.copy_tree(local, original_local)
+                copytree(local, original_local, dirs_exist_ok=True)
                 shutil.rmtree(temp_parent)
 
     def get_file(self, remote, offset=None, length=None, timeout=None):
         """Pull file from device and return the file's content
 
         :param str remote: The path of the remote file.
         :param offset: If specified, return only content beyond this offset.
         :param length: If specified, limit content length accordingly.
diff --git a/testing/mozbase/mozdevice/mozdevice/remote_process_monitor.py b/testing/mozbase/mozdevice/mozdevice/remote_process_monitor.py
--- a/testing/mozbase/mozdevice/mozdevice/remote_process_monitor.py
+++ b/testing/mozbase/mozdevice/mozdevice/remote_process_monitor.py
@@ -130,17 +130,17 @@ class RemoteProcessMonitor:
                     if message.get("action") == "test_start":
                         self.last_test_seen = message["test"]
                     elif message.get("action") == "test_end":
                         self.last_test_seen = "{} (finished)".format(message["test"])
                     elif message.get("action") == "suite_end":
                         self.last_test_seen = "Last test finished"
                     elif message.get("action") == "log":
                         line = message["message"].strip()
-                        m = re.match(".*:\s*(\d*)", line)
+                        m = re.match(r".*:\s*(\d*)", line)
                         if m:
                             try:
                                 val = int(m.group(1))
                                 if "Passed:" in line:
                                     self.counts["pass"] += val
                                     self.last_test_seen = "Last test finished"
                                 elif "Failed:" in line:
                                     self.counts["fail"] += val
diff --git a/testing/mozbase/mozrunner/mozrunner/application.py b/testing/mozbase/mozrunner/mozrunner/application.py
--- a/testing/mozbase/mozrunner/mozrunner/application.py
+++ b/testing/mozbase/mozrunner/mozrunner/application.py
@@ -1,16 +1,16 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os
 import posixpath
 from abc import ABCMeta, abstractmethod
-from distutils.spawn import find_executable
+from shutil import which
 
 import six
 from mozdevice import ADBDeviceFactory
 from mozprofile import (
     ChromeProfile,
     ChromiumProfile,
     FirefoxProfile,
     Profile,
@@ -46,17 +46,17 @@ class RemoteContext(object):
     profile_class = Profile
     _bindir = None
     remote_test_root = ""
     remote_process = None
 
     @property
     def bindir(self):
         if self._bindir is None:
-            paths = [find_executable("emulator")]
+            paths = [which("emulator")]
             paths = [p for p in paths if p is not None if os.path.isfile(p)]
             if not paths:
                 self._bindir = ""
             else:
                 self._bindir = os.path.dirname(paths[0])
         return self._bindir
 
     @property
@@ -83,17 +83,17 @@ class RemoteContext(object):
         return self._remote_profile
 
     def which(self, binary):
         paths = os.environ.get("PATH", {}).split(os.pathsep)
         if self.bindir is not None and os.path.abspath(self.bindir) not in paths:
             paths.insert(0, os.path.abspath(self.bindir))
             os.environ["PATH"] = os.pathsep.join(paths)
 
-        return find_executable(binary)
+        return which(binary)
 
     @abstractmethod
     def stop_application(self):
         """Run (device manager) command to stop application."""
         pass
 
 
 devices = {}