Orderfile: import csv

Not having csv imported causes the memory benchmark results to be
reported as: "Error: global name 'csv' is not defined". Perhaps in the
past the module was imported from some other file.

Adding the necessary import will not fix the bug, rather will make us
closer to see how bad the coverage-for-memory has been recently. When
the bug gets fixed, it would be interesting to see whether it affected
the memory usage.

Bug: 1117184
Change-Id: I6ee502298e1d88aadbeb7a5866128743557cd753
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2401039
Commit-Queue: Egor Pasko <pasko@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Auto-Submit: Egor Pasko <pasko@chromium.org>
Reviewed-by: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805280}

diff --git a/tools/cygprofile/orderfile_generator_backend.py b/tools/cygprofile/orderfile_generator_backend.py
index 00d9f3c..a0d536e 100755
--- a/tools/cygprofile/orderfile_generator_backend.py
+++ b/tools/cygprofile/orderfile_generator_backend.py

@@ -10,13 +10,13 @@
 to page in less code during start-up.
 
 Example usage:
-  tools/cygprofile/orderfile_generator_backend.py -l 20 -j 1000 --use-goma \
-    --target-arch=arm
+  tools/cygprofile/orderfile_generator_backend.py --use-goma --target-arch=arm
 """
 
 from __future__ import print_function
 
 import argparse
+import csv
 import hashlib
 import json
 import glob