Walk through files in parse_llvm_coverage.py instead of using 'git ls-files'

tools/parse_llvm_coverage.py

 #!/usr/bin/env python
 # Copyright (c) 2015 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.
 
 
 """Parse an LLVM coverage report to generate useable results."""
 
 
 import argparse
@@ skipping 41 matching lines @@
     print >> sys.stderr, ('WARNING: multiple matches for %s; skipping:\n\t%s'
                           % (new_file, '\n\t'.join(matched)))
   return None
 
 
 def _get_per_file_per_line_coverage(report):
   """Return a dict whose keys are file names and values are coverage data.
 
   Values are lists which take the form (lineno, coverage, code).
   """
-  all_files = subprocess.check_output(['git', 'ls-files']).splitlines()
+  all_files = []
+  for root, dirs, files in os.walk(os.getcwd()):
+    if 'third_party/externals' in root:
+      continue
+    files = [f for f in files if not (f[0] == '.' or f.endswith('.pyc'))]
+    dirs[:] = [d for d in dirs if not d[0] == '.']
+    for name in files:
+      all_files.append(os.path.join(root[(len(os.getcwd()) + 1):], name))
+  all_files.sort()
+
   lines = report.splitlines()
   current_file = None
   file_lines = []
   files = {}
   not_checked_in = '%' # Use this as the file name for not-checked-in files.
   for line in lines:
     m = re.match('([a-zA-Z0-9\./_-]+):', line)
     if m:
       if current_file and current_file != not_checked_in:
         files[current_file] = file_lines
@@ skipping 122 matching lines @@
     per_file = _get_per_file_summaries(line_by_line)
 
     # Write results.
     format_results = _nanobench_json(per_file, properties, key)
     with open(args.nanobench, 'w') as f:
       json.dump(format_results, f)
 
 
 if __name__ == '__main__':
   main()