Auto-CC ipc-security-reviews@ when changing IPC-related files.

Bug: 786386
Change-Id: I28d5809389aa86ee274b17725ca5312d4b8bb3ae
Reviewed-on: https://chromium-review.googlesource.com/776411
Commit-Queue: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#518329}

PRESUBMIT.py

@@ -1508,11 +1508,15 @@ def _MatchesFile(input_api, patterns, path):
   return False
 
 
-def _CheckIpcOwners(input_api, output_api):
-  """Checks that affected files involving IPC have an IPC OWNERS rule.
+def _GetOwnersFilesToCheckForIpcOwners(input_api):
+  """Gets a list of OWNERS files to check for correct security owners.
 
-  Whether or not a file affects IPC is determined by a simple whitelist of
-  filename patterns."""
+  Returns:
+    A dictionary mapping an OWNER file to the list of OWNERS rules it must
+    contain to cover IPC-related files with noparent reviewer rules.
+  """
+  # Whether or not a file affects IPC is (mostly) determined by a simple list
+  # of filename patterns.
   file_patterns = [
       # Legacy IPC:
       '*_messages.cc',
@@ -1610,8 +1614,20 @@ def _CheckIpcOwners(input_api, output_api):
         AddPatternToCheck(f, pattern)
         break
 
-  # Now go through the OWNERS files we collected, filtering out rules that are
-  # already present in that OWNERS file.
+  return to_check
+
+
+def _CheckIpcOwners(input_api, output_api):
+  """Checks that affected files involving IPC have an IPC OWNERS rule."""
+  to_check = _GetOwnersFilesToCheckForIpcOwners(input_api)
+
+  if to_check:
+    # If there are any OWNERS files to check, there are IPC-related changes in
+    # this CL. Auto-CC the review list.
+    output_api.AppendCC('ipc-security-reviews@chromium.org')
+
+  # Go through the OWNERS files to check, filtering out rules that are already
+  # present in that OWNERS file.
   for owners_file, patterns in to_check.iteritems():
     try:
       with file(owners_file) as f:

PRESUBMIT_test_mocks.py

@@ -131,6 +131,12 @@ class MockOutputApi(object):
       MockOutputApi.PresubmitResult.__init__(self, message, items, long_text)
       self.type = 'promptOrNotify'
 
+  def __init__(self):
+    self.more_cc = []
+
+  def AppendCC(self, more_cc):
+    self.more_cc.extend(more_cc)
+
 
 class MockFile(object):
   """Mock class for the File class.