[Autotest] Adds a milestone and Os-Chrome label to autofiled bugs.

TEST=Filed bugs on fake project with mentioned labels.
     Made sure we don't assert with invalid build strings.
BUG=None

Change-Id: Icd6dbb0c9dc47135dcf3f9d2d9e9ce1a547cf73b
Reviewed-on: https://gerrit.chromium.org/gerrit/48758
Commit-Queue: Prashanth Balasubramanian <beeps@chromium.org>
Reviewed-by: Prashanth Balasubramanian <beeps@chromium.org>
Tested-by: Prashanth Balasubramanian <beeps@chromium.org>
diff --git a/test_suites/control.perf_v2 b/test_suites/control.perf_v2
index 929b487..1d66171 100644
--- a/test_suites/control.perf_v2
+++ b/test_suites/control.perf_v2
@@ -32,7 +32,7 @@
 # filing bugs on tests that are a part of this suite. If left unspecified
 # the bug filer will fallback to it's defaults.
 _BUG_TEMPLATE = {
-    'labels': ['OS-Chrome','Type-Bug', 'perf-infra'],
+    'labels': ['Type-Bug', 'perf-infra'],
     'owner': '',
     'status': None,
     'summary': None,