Finish up flake8 conversion.

Change-Id: I5034f19d5f9b20ad2b4569455273c730b1efec08
diff --git a/run_tests.sh b/run_tests.sh
index 6fcdd90..56a6e6e 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -109,7 +109,7 @@
 
 function run_pep8 {
   echo "Running pep8 ..."
-  ${wrapper} tools/check_source.sh
+  ${wrapper} flake8
 }
 
 function run_coverage_start {