Extract supported codecs from CDM component manifest.

chrome/browser/component_updater/component_unpacker.h

 // 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.
 
 #ifndef CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_UNPACKER_H_
 #define CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_UNPACKER_H_
 
 #include <string>
 #include <vector>
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
+#include "base/json/json_file_value_serializer.h"
+#include "base/memory/scoped_ptr.h"
 
 class ComponentInstaller;
 class ComponentPatcher;
 
+// Deserializes the CRX manifest. The top level must be a dictionary.
+scoped_ptr<base::DictionaryValue> ReadManifest(
+    const base::FilePath& unpack_path);
+
 // In charge of unpacking the component CRX package and verifying that it is
 // well formed and the cryptographic signature is correct. If there is no
 // error the component specific installer will be invoked to proceed with
 // the component installation or update.
 //
 // This class should be used only by the component updater. It is inspired
 // and overlaps with code in the extension's SandboxedUnpacker.
 // The main differences are:
 // - The public key hash is full SHA256.
 // - Does not use a sandboxed unpacker. A valid component is fully trusted.
@@ skipping 39 matching lines @@
 
   int extended_error() const { return extended_error_; }
 
  private:
   base::FilePath unpack_path_;
   Error error_;
   int extended_error_;  // Provides additional error information.
 };
 
 #endif  // CHROME_BROWSER_COMPONENT_UPDATER_COMPONENT_UNPACKER_H_