In https://codereview.chromium.org/2069803003/, the entire //ipc/mojo directory is deleted. However, the presubmit check fails with:

** Presubmit ERRORS **
Found changes to IPC files without a security OWNER!

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ipc/mojo/OWNERS is missing the following lines:

per-file *.mojom=set noparent
per-file *.mojom=file://ipc/SECURITY_OWNERS
per-file *_param_traits*.*=set noparent
per-file *_param_traits*.*=file://ipc/SECURITY_OWNERS

for changed files:
  ipc/mojo/ipc.mojom
  ipc/mojo/ipc_mojo_param_traits.cc
  ipc/mojo/ipc_mojo_param_traits.h
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