Move StringPiece into the base namespace. It is colliding

base/file_path.h

 // Copyright (c) 2008 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.
 
 // FilePath is a container for pathnames stored in a platform's native string
 // type, providing containers for manipulation in according with the
 // platform's conventions for pathnames.  It supports the following path
 // types:
 //
 //                   POSIX            Windows
@@ skipping 169 matching lines @@
   FilePath RemoveExtension() const;
 
   // Inserts |suffix| after the file name portion of |path| but before the
   // extension.  Returns "" if BaseName() == "." or "..".
   // Examples:
   // path == "C:\pics\jojo.jpg" suffix == " (1)", returns "C:\pics\jojo (1).jpg"
   // path == "jojo.jpg"         suffix == " (1)", returns "jojo (1).jpg"
   // path == "C:\pics\jojo"     suffix == " (1)", returns "C:\pics\jojo (1)"
   // path == "C:\pics.old\jojo" suffix == " (1)", returns "C:\pics.old\jojo (1)"
   FilePath InsertBeforeExtension(const StringType& suffix) const;
-  FilePath InsertBeforeExtensionASCII(const StringPiece& suffix) const;
+  FilePath InsertBeforeExtensionASCII(const base::StringPiece& suffix) const;
 
   // Replaces the extension of |file_name| with |extension|.  If |file_name|
   // does not have an extension, them |extension| is added.  If |extension| is
   // empty, then the extension is removed from |file_name|.
   // Returns "" if BaseName() == "." or "..".
   FilePath ReplaceExtension(const StringType& extension) const;
 
   // Returns true if the file path matches the specified extension. The test is
   // case insensitive. Don't forget the leading period if appropriate.
   bool MatchesExtension(const StringType& extension) const;
 
   // Returns a FilePath by appending a separator and the supplied path
   // component to this object's path.  Append takes care to avoid adding
   // excessive separators if this object's path already ends with a separator.
   // If this object's path is kCurrentDirectory, a new FilePath corresponding
   // only to |component| is returned.  |component| must be a relative path;
   // it is an error to pass an absolute path.
   FilePath Append(const StringType& component) const WARN_UNUSED_RESULT;
   FilePath Append(const FilePath& component) const WARN_UNUSED_RESULT;
 
   // Although Windows StringType is std::wstring, since the encoding it uses for
   // paths is well defined, it can handle ASCII path components as well.
   // Mac uses UTF8, and since ASCII is a subset of that, it works there as well.
   // On Linux, although it can use any 8-bit encoding for paths, we assume that
   // ASCII is a valid subset, regardless of the encoding, since many operating
   // system paths will always be ASCII.
-  FilePath AppendASCII(const StringPiece& component) const WARN_UNUSED_RESULT;
+  FilePath AppendASCII(const base::StringPiece& component)
+      const WARN_UNUSED_RESULT;
 
   // Returns true if this FilePath contains an absolute path.  On Windows, an
   // absolute path begins with either a drive letter specification followed by
   // a separator character, or with two separator characters.  On POSIX
   // platforms, an absolute path begins with a separator character.
   bool IsAbsolute() const;
 
   // Returns a copy of this FilePath that does not end with a trailing
   // separator.
   FilePath StripTrailingSeparators() const;
@@ skipping 51 matching lines @@
 namespace stdext {
 
 inline size_t hash_value(const FilePath& f) {
   return hash_value(f.value());
 }
 
 }  // namespace stdext
 #endif  // COMPILER
 
 #endif  // BASE_FILE_PATH_H_