Reland of PyLint fixes for tools-webrtc and webrtc/tools (patchset #1 id:1 of https://codereview.webrtc.org/2737233003/ )

Reason for revert:
Fixing errors for reland. I have tested that this does not make Chromium video quality tests fail.

Original issue's description:
> Revert of PyLint fixes for tools-webrtc and webrtc/tools (patchset #3 id:40001 of https://codereview.webrtc.org/2736233003/ )
>
> Reason for revert:
> Fails video quality tests in Chrome:  http://build.chromium.org/p/chromium.webrtc.fyi/builders/Win10%20Tester/builds/6568
> I should have looked more closer at those :(
>
> Original issue's description:
> > PyLint fixes for tools-webrtc and webrtc/tools
> >
> > Fix a lot of errors before bringing in the new config in
> > https://codereview.webrtc.org/2737963003/
> >
> > BUG=webrtc:7303
> > NOTRY=True
> >
> > Review-Url: https://codereview.webrtc.org/2736233003
> > Cr-Commit-Position: refs/heads/master@{#17137}
> > Committed: https://chromium.googlesource.com/external/webrtc/+/f5318e1f391859c82aaa47b297429e50f41f6b3c
>
> TBR=oprypin@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:7303
>
> Review-Url: https://codereview.webrtc.org/2737233003
> Cr-Commit-Position: refs/heads/master@{#17142}
> Committed: https://chromium.googlesource.com/external/webrtc/+/94f4d9effc3fa1ee6a6a48a7bbdef6684defd1dc

NOTRY=true
BUG=webrtc:7312

Review-Url: https://codereview.webrtc.org/2741733003
Cr-Commit-Position: refs/heads/master@{#17541}
diff --git a/tools-webrtc/get_landmines.py b/tools-webrtc/get_landmines.py
index d2087bb..4786ec4 100755
--- a/tools-webrtc/get_landmines.py
+++ b/tools-webrtc/get_landmines.py
@@ -15,19 +15,16 @@
 import os
 import sys
 
-script_dir = os.path.dirname(os.path.realpath(__file__))
-checkout_root = os.path.abspath(os.path.join(script_dir, os.pardir))
-sys.path.insert(0, os.path.join(checkout_root, 'build'))
+SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
+CHECKOUT_ROOT = os.path.abspath(os.path.join(SCRIPT_DIR, os.pardir))
+sys.path.insert(0, os.path.join(CHECKOUT_ROOT, 'build'))
 import landmine_utils
 
 
-distributor = landmine_utils.distributor
-gyp_defines = landmine_utils.gyp_defines
-gyp_msvs_version = landmine_utils.gyp_msvs_version
-platform = landmine_utils.platform
+platform = landmine_utils.platform  # pylint: disable=invalid-name
 
 
-def print_landmines():
+def print_landmines():  # pylint: disable=invalid-name
   """
   ALL LANDMINES ARE EMITTED FROM HERE.
   """