Add CdmFileIOProvider interface for use by cdm_adapter

media/cdm/cdm_file_io.cc

Index: media/cdm/cdm_file_io.cc
diff --git a/media/cdm/cdm_allocator.cc b/media/cdm/cdm_file_io.cc
similarity index 67%
copy from media/cdm/cdm_allocator.cc
copy to media/cdm/cdm_file_io.cc
index 52e722c35f1ed39e26452b6fca184eec0d83967f..6a61084df30cc436563e9fc247862bd9f48b9812 100644
--- a/media/cdm/cdm_allocator.cc
+++ b/media/cdm/cdm_file_io.cc
@@ -2,12 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "media/cdm/cdm_allocator.h"
+#include "media/cdm/cdm_file_io.h"
 
 namespace media {
 
-CdmAllocator::CdmAllocator() {}
+CdmFileIO::CdmFileIO() {}
 
-CdmAllocator::~CdmAllocator() {}
+CdmFileIO::~CdmFileIO() {}
 
 }  // namespace media