Added function to get native path case on Windows and OSX.

tools/isolate/data/trace_inputs/child2.py

Index: tools/isolate/data/trace_inputs/child2.py
diff --git a/tools/isolate/data/trace_inputs/child2.py b/tools/isolate/data/trace_inputs/child2.py
index cfcac3f3ec677d9483e34070e23c3362a5bc0ebd..6b1836477b28203c78c651219e1f1873ca51fa2f 100644
--- a/tools/isolate/data/trace_inputs/child2.py
+++ b/tools/isolate/data/trace_inputs/child2.py
@@ -2,11 +2,26 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import sys
 import time
 
-print 'child2'
-# Introduce a race condition with the parent so the parent may have a chance
-# to exit before the child. Will be random.
-time.sleep(.01)
-# Do not do anything with it.
-open('test_file.txt')
+
+def main():
+  print 'child2'
+  # Introduce a race condition with the parent so the parent may have a chance
+  # to exit before the child. Will be random.
+  time.sleep(.01)
+  # Do not do anything with it.
+  open('test_file.txt')
+  # Check for case-insensitive file system. This happens on Windows and OSX.
+  try:
+    open('Test_File.txt')
+  except OSError:
+    # Pass on other OSes since this code assumes only win32 has case-insensitive
+    # path. This is not strictly true.
+    if sys.platform not in ('darwin', 'win32'):
+      raise
+
+
+if __name__ == '__main__':
+  sys.exit(main())