Reland "[test] Fix cctest path separators on Windows"

test/test262/testcfg.py

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 48 matching lines @@
     tests = []
     for dirname, dirs, files in os.walk(self.testroot):
       for dotted in [x for x in dirs if x.startswith(".")]:
         dirs.remove(dotted)
       if context.noi18n and "intl402" in dirs:
         dirs.remove("intl402")
       dirs.sort()
       files.sort()
       for filename in files:
         if filename.endswith(".js"):
-          testname = os.path.join(dirname[len(self.testroot) + 1:],
-                                  filename[:-3])
+          fullpath = os.path.join(dirname, filename)
+          relpath = fullpath[len(self.testroot) + 1 : -3]
+          testname = relpath.replace(os.path.sep, "/")
           case = testcase.TestCase(self, testname)
           tests.append(case)
     return tests
 
   def GetFlagsForTestCase(self, testcase, context):
     return (testcase.flags + context.mode_flags + self.harness +
             [os.path.join(self.testroot, testcase.path + ".js")])
 
   def GetSourceForTest(self, testcase):
     filename = os.path.join(self.testroot, testcase.path + ".js")
@@ skipping 48 matching lines @@
         # Magic incantation to allow longer path names on Windows.
         archive.extractall(u"\\\\?\\%s" % self.root)
       else:
         archive.extractall(self.root)
       os.rename(os.path.join(self.root, "tc39-test262-%s" % revision),
                 directory_name)
 
 
 def GetSuite(name, root):
   return Test262TestSuite(name, root)