Re-enabling CheckOrphanHeaders

NOTRY=True

Bug: chromium:611808
Change-Id: I354ebe340a0cf70be8cd08b88adbb0f767070e1e
Reviewed-on: https://webrtc-review.googlesource.com/1574
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19853}
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 66d6892..fcac22f 100755
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -619,10 +619,7 @@
   results.extend(CheckJSONParseErrors(input_api, output_api))
   results.extend(RunPythonTests(input_api, output_api))
   results.extend(CheckUsageOfGoogleProtobufNamespace(input_api, output_api))
-  # TODO(mbonadei): re-enable after the migration from src/webrtc to src/
-  #   in order to avoid to trigger an error for each orphan header (we are
-  #   moving all of them).
-  # results.extend(CheckOrphanHeaders(input_api, output_api))
+  results.extend(CheckOrphanHeaders(input_api, output_api))
   # TODO(mbonadei): check before re-enable because it seems it is reporting
   #   some false positives.
   # results.extend(CheckNewLineAtTheEndOfProtoFiles(input_api, output_api))