Add media file validation to utility process

media/filters/file_data_source.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 MEDIA_FILTERS_FILE_DATA_SOURCE_H_
 #define MEDIA_FILTERS_FILE_DATA_SOURCE_H_
 
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/files/memory_mapped_file.h"
+#include "base/platform_file.h"
 #include "media/base/data_source.h"
 
 namespace media {
 
 // Basic data source that treats the URL as a file path, and uses the file
 // system to read data for a media pipeline.
 class MEDIA_EXPORT FileDataSource : public DataSource {
  public:
   FileDataSource();
   virtual ~FileDataSource();
 
   bool Initialize(const base::FilePath& file_path);
+  bool InitializeFromPlatformFile(const base::PlatformFile& file);
 
   // Implementation of DataSource.
   virtual void set_host(DataSourceHost* host) OVERRIDE;
   virtual void Stop(const base::Closure& callback) OVERRIDE;
   virtual void Read(int64 position, int size, uint8* data,
                     const DataSource::ReadCB& read_cb) OVERRIDE;
   virtual bool GetSize(int64* size_out) OVERRIDE;
   virtual bool IsStreaming() OVERRIDE;
   virtual void SetBitrate(int bitrate) OVERRIDE;
 
   // Unit test helpers. Recreate the object if you want the default behaviour.
   void force_read_errors_for_testing() { force_read_errors_ = true; }
   void force_streaming_for_testing() { force_streaming_ = true; }
 
  private:
   // Informs the host of changes in total and buffered bytes.
   void UpdateHostBytes();
 
   base::MemoryMappedFile file_;
 
   bool force_read_errors_;
   bool force_streaming_;
 
   DISALLOW_COPY_AND_ASSIGN(FileDataSource);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_FILE_DATA_SOURCE_H_