Add closure_compilation to `git cl try` for CLs that touch resources

chrome/browser/resources/PRESUBMIT.py

Index: chrome/browser/resources/PRESUBMIT.py
diff --git a/chrome/browser/resources/PRESUBMIT.py b/chrome/browser/resources/PRESUBMIT.py
index 6d60a3a922829212ccbaaba2e03fa37454310b48..2e853aa7e2d53876c1c0d6c417c240315b3431ee 100644
--- a/chrome/browser/resources/PRESUBMIT.py
+++ b/chrome/browser/resources/PRESUBMIT.py
@@ -120,3 +120,11 @@ def PostUploadHook(cl, change, output_api):
   rietveld_obj.update_description(cl.issue, new_description)
   return [output_api.PresubmitNotifyResult(
       'Automatically added optional Closure bots to run on CQ.')]
+
+
+def GetPreferredTryMasters(project, change):
+  return {
+    'tryserver.chromium.linux': {
+      'closure_compilation': set(['defaulttests']),
+    },
+  }