Android: Turn on pylint for more files

Now that crbug.com/1100664 is fixed, pylint can be turned on for more
build/android scripts.

Bug: 1100664
Change-Id: Id68cb625ae966184d92f115403539231bfa7f308
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3570542
Auto-Submit: Peter Wen <[email protected]>
Reviewed-by: Samuel Huang <[email protected]>
Commit-Queue: Samuel Huang <[email protected]>
Cr-Commit-Position: refs/heads/main@{#989040}
diff --git a/build/android/fast_local_dev_server.py b/build/android/fast_local_dev_server.py
index 761338f6..055fb9a 100755
--- a/build/android/fast_local_dev_server.py
+++ b/build/android/fast_local_dev_server.py
@@ -110,6 +110,7 @@
         if line.startswith('procs_running'):
           return int(line.rstrip().split()[1])
     assert False, 'Could not read /proc/stat'
+    return 0
 
   def _maybe_start_tasks(self):
     if self._deactivated:
@@ -174,6 +175,8 @@
       # TODO(wnwen): Use ionice to reduce resource consumption.
       TaskStats.add_process()
       log(f'STARTING {self.name}')
+      # This use of preexec_fn is sufficiently simple, just one os.nice call.
+      # pylint: disable=subprocess-popen-preexec-fn
       self._proc = subprocess.Popen(
           self.cmd,
           stdout=subprocess.PIPE,
@@ -326,6 +329,7 @@
     sock.bind(server_utils.SOCKET_ADDRESS)
     sock.listen()
     _process_requests(sock)
+  return 0
 
 
 if __name__ == '__main__':