Backed out 4 changesets (bug 1460402) for breaking taskcluster images. CLOSED TREE

Backed out changeset 5b40f3f18f42 (bug 1460402)
Backed out changeset 17526c61b995 (bug 1460402)
Backed out changeset e1caff997e5a (bug 1460402)
Backed out changeset 06ceda084d69 (bug 1460402)

tools/lint/python/flake8.py

@@ -6,13 +6,13 @@ import json
 import os
 import platform
 import signal
+import subprocess
 import sys
 from collections import defaultdict
 
 from mozprocess import ProcessHandlerMixin
 
 from mozlint import result
-from mozlint.util import pip
 from mozlint.pathutils import get_ancestors_by_name
 
 
@@ -98,6 +98,32 @@ class Flake8Process(ProcessHandlerMixin):
         signal.signal(signal.SIGINT, orig)
 
 
+def _run_pip(*args):
+    """
+    Helper function that runs pip with subprocess
+    """
+    try:
+        subprocess.check_output([os.path.join(bindir, 'pip')] + list(args),
+                                stderr=subprocess.STDOUT)
+        return True
+    except subprocess.CalledProcessError as e:
+        print(e.output)
+        return False
+
+
+def reinstall_flake8():
+    """
+    Try to install flake8 at the target version, returns True on success
+    otherwise prints the otuput of the pip command and returns False
+    """
+    if _run_pip('install', '-U',
+                '--require-hashes', '-r',
+                FLAKE8_REQUIREMENTS_PATH):
+        return True
+
+    return False
+
+
 def run_process(config, cmd):
     proc = Flake8Process(config, cmd)
     proc.run()
@@ -109,7 +135,7 @@ def run_process(config, cmd):
 
 
 def setup(root):
-    if not pip.reinstall_program(FLAKE8_REQUIREMENTS_PATH):
+    if not reinstall_flake8():
         print(FLAKE8_INSTALL_ERROR)
         return 1