Treat '...' as a non-parent path component outside of Windows.

base/files/file_path.cc

 // Copyright (c) 2012 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.
 
 #include "base/files/file_path.h"
 
 #include <string.h>
 #include <algorithm>
 
 #include "base/basictypes.h"
@@ skipping 544 matching lines @@
   FilePath new_path(path_);
   new_path.StripTrailingSeparatorsInternal();
 
   return new_path;
 }
 
 bool FilePath::ReferencesParent() const {
   std::vector<StringType> components;
   GetComponents(&components);
 
-  std::vector<StringType>::const_iterator it = components.begin();
-  for (; it != components.end(); ++it) {
-    const StringType& component = *it;
+  for (const StringType& component : components) {
+#if defined(OS_WIN)
     // Windows has odd, undocumented behavior with path components containing
     // only whitespace and . characters. So, if all we see is . and
     // whitespace, then we treat any .. sequence as referencing parent.
-    // For simplicity we enforce this on all platforms.
     if (component.find_first_not_of(FILE_PATH_LITERAL(". \n\r\t")) ==
             std::string::npos &&
         component.find(kParentDirectory) != std::string::npos) {
+      // Add a debug-only warning so Windows-specific bot failures are easier to
+      // diagnose.
+      DLOG_IF(WARNING, component != kParentDirectory)
+          << "Rejecting Windows-specific path component.";
       return true;
     }
+#else
+    if (component == kParentDirectory)
+      return true;
+#endif
   }
   return false;
 }
 
 #if defined(OS_POSIX)
 // See file_path.h for a discussion of the encoding of paths on POSIX
 // platforms.  These encoding conversion functions are not quite correct.
 
 string16 FilePath::LossyDisplayName() const {
   return WideToUTF16(SysNativeMBToWide(path_));
@@ skipping 725 matching lines @@
 #endif
 }
 
 #if defined(OS_ANDROID)
 bool FilePath::IsContentUri() const {
   return StartsWith(path_, "content://", base::CompareCase::INSENSITIVE_ASCII);
 }
 #endif
 
 }  // namespace base