Add script to mass add a new #include.

cheddar_monkey.py

Index: cheddar_monkey.py
diff --git a/cheddar_monkey.py b/cheddar_monkey.py
new file mode 100755
index 0000000000000000000000000000000000000000..6c5e70f231a7d9ff32f6af72d260fd89a2313d45
--- /dev/null
+++ b/cheddar_monkey.py
@@ -0,0 +1,59 @@
+#!/usr/bin/env python
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import os
+import re
+import subprocess
+import sys
+
+# Clang errors look like this:
+# ../../base/test/test_discardable_memory_allocator.cc:22:5: error: use of undeclared identifier 'DCHECK'
+_CLANG_ERROR_RE = re.compile('(?P<path>[^:]+):\d+:\d+: error: .+')
+
+
+def FindFirstFileWithError(output):
+  for line in output.splitlines():
+    match = _CLANG_ERROR_RE.match(line)
+    if match:
+      return match.group('path')
+
+
+def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument('--header', required=True)
+  parser.add_argument('--build-dir', default='.')
+  parser.add_argument('additional_build_args', nargs='*')
+  args = parser.parse_args()
+
+  while True:
+    try:
+      ninja_args = ['ninja']
+      ninja_args.extend(['-C', args.build_dir])
+      ninja_args.extend(args.additional_build_args)
+      print 'Running %s' % ninja_args
+      subprocess.check_output(ninja_args)
+    except subprocess.CalledProcessError as e:
+      print 'Got a compile error!'
+      bad_file = FindFirstFileWithError(e.output)
+      if not bad_file:
+        print 'Something bad happened!'
+        print e.output
+        return 2
+      bad_file_path = os.path.join(args.build_dir, bad_file)
+      add_header_args = ['python', 'tools/clang/pass_to_move/add_header.py',
+                         '--header', args.header, bad_file_path]
+      print 'Inserting header with command %s' % add_header_args
+      subprocess.check_call(add_header_args)
+      continue
+    except Exception as e:
+      print 'Something weird happened: %s' % e
+      return 1
+    print 'Probably done! \(^.^)/'
+    break
+
+
+if __name__ == '__main__':
+  sys.exit(main())