zephyr_mirror: Use json if simplejson is not available.

(imported from commit 4b5f6ff71067cd2697c864c715afbb3b9dd19302)

bots/zephyr_mirror_backend.py

@@ -22,7 +22,10 @@
 # SOFTWARE.
 
 import sys
+try:
     import simplejson
+except ImportError:
+    import json as simplejson
 import re
 import time
 import subprocess

tools/check-all

@@ -79,7 +79,10 @@ try:
     # pyflakes writes some output (like syntax errors) to stderr. :/
     for pipe in (pyflakes.stdout, pyflakes.stderr):
         for ln in pipe:
-            if options.full or not 'imported but unused' in ln:
+            if options.full or not \
+                    ('imported but unused' in ln or
+                     ("zephyr_mirror_backend.py:" in ln and
+                      "redefinition of unused 'simplejson' from line" in ln)):
                 sys.stdout.write(ln)
                 failed = True