Change ppapi C++ comment style into C.

ppapi/c/dev/ppb_file_io_trusted_dev.h

-// Copyright (c) 2010 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.
-
+/* Copyright (c) 2010 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_DEV_PPB_FILE_IO_TRUSTED_DEV_H_
 #define PPAPI_C_DEV_PPB_FILE_IO_TRUSTED_DEV_H_
 
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_stdint.h"
 
 struct PP_CompletionCallback;
 
 #define PPB_FILEIOTRUSTED_DEV_INTERFACE "PPB_FileIOTrusted(Dev);0.2"
 
@@ skipping 20 matching lines @@
                            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_DEV_PPB_FILE_IO_TRUSTED_DEV_H_
+#endif  /* PPAPI_C_DEV_PPB_FILE_IO_TRUSTED_DEV_H_ */
+