Fix harmless warning in setup_third_party

webkit/support/setup_third_party.py

Index: webkit/support/setup_third_party.py
diff --git a/webkit/support/setup_third_party.py b/webkit/support/setup_third_party.py
index f3cf719c5b8590eec9cc83a7bc2baad9201f0185..9d3dfee1e43018c9be39ae6d412dd3d9837f1853 100644
--- a/webkit/support/setup_third_party.py
+++ b/webkit/support/setup_third_party.py
@@ -14,7 +14,8 @@ def GetHeaderFilesInDir(dir_path):
   """Return a list of all header files in dir_path."""
   all_files = []
   for root, dirs, files in os.walk(dir_path):
-    all_files.extend([os.path.join(root, f) for f in files if f.endswith('.h')])
+    all_files.extend([os.path.join(root, f).replace(os.sep, '/')
+                      for f in files if f.endswith('.h')])
   return all_files