Sang's initial CL for moving the file interface out of dev.

ppapi/c/trusted/ppb_file_io_trusted.h

Index: ppapi/c/trusted/ppb_file_io_trusted.h
===================================================================
--- ppapi/c/trusted/ppb_file_io_trusted.h	(revision 0)
+++ ppapi/c/trusted/ppb_file_io_trusted.h	(revision 0)
@@ -0,0 +1,47 @@
+/* Copyright (c) 2011 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 PPAPI_C_PPB_FILE_IO_TRUSTED_H_
+#define PPAPI_C_PPB_FILE_IO_TRUSTED_H_
+
+#include "ppapi/c/pp_resource.h"
+#include "ppapi/c/pp_stdint.h"
+
+struct PP_CompletionCallback;
+
+#define PPB_FILEIOTRUSTED_INTERFACE_0_3 "PPB_FileIOTrusted(Dev);0.3"
+#define PPB_FILEIOTRUSTED_INTERFACE PPB_FILEIOTRUSTED_INTERFACE_0_3
+
+// Available only to trusted implementations.
+struct PPB_FileIOTrusted {
+  // Returns a file descriptor corresponding to the given FileIO object. On
+  // Windows, returns a HANDLE; on all other platforms, returns a POSIX file
+  // descriptor. The FileIO object must have been opened with a successful
+  // call to FileIO::Open.  The file descriptor will be closed automatically
+  // when the FileIO object is closed or destroyed.
+  int32_t (*GetOSFileDescriptor)(PP_Resource file_io);
+
+  // Notifies the browser that underlying file will be modified.  This gives
+  // the browser the opportunity to apply quota restrictions and possibly
+  // return an error to indicate that the write is not allowed.
+  int32_t (*WillWrite)(PP_Resource file_io,
+                       int64_t offset,
+                       int32_t bytes_to_write,
+                       struct PP_CompletionCallback callback);
+
+  // Notifies the browser that underlying file will be modified.  This gives
+  // the browser the opportunity to apply quota restrictions and possibly
+  // return an error to indicate that the write is not allowed.
+  int32_t (*WillSetLength)(PP_Resource file_io,
+                           int64_t length,
+                           struct PP_CompletionCallback callback);
+
+  // TODO(darin): Maybe unify the above into a single WillChangeFileSize
+  // method?  The above methods have the advantage of mapping to PPB_FileIO
+  // Write and SetLength calls.  WillChangeFileSize would require the caller to
+  // compute the file size resulting from a Write call, which may be
+  // undesirable.
+};
+
+#endif  /* PPAPI_C_PPB_FILE_IO_TRUSTED_H_ */