Move CrxFile, FileReader, ExtensionResource to src/extensions.

extensions/common/id_util.h

+// Copyright (c) 2013 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.
+
+#ifndef EXTENSIONS_COMMON_ID_UTIL_H_
+#define EXTENSIONS_COMMON_ID_UTIL_H_
+
+#include <string>
+
+namespace base {
+class FilePath;
+}
+
+namespace extensions {
+namespace id_util {
+
+// The number of bytes in a legal id.
+extern const size_t kIdSize;
+
+// Generates an extension ID from arbitrary input. The same input string will
+// always generate the same output ID.
+std::string GenerateId(const std::string& input);
+
+// Generate an ID for an extension in the given path.
+// Used while developing extensions, before they have a key.
+std::string GenerateIdForPath(const base::FilePath& path);
+
+// Normalize the path for use by the extension. On Windows, this will make
+// sure the drive letter is uppercase.
+base::FilePath MaybeNormalizePath(const base::FilePath& path);
+
+}  // namespace id_util
+}  // namespace extensions
+
+#endif  // EXTENSIONS_COMMON_ID_UTIL_H_