[Lazarus] TStringStream changes

[Michael Van Canneyt]

Hello,

TStringStream now observes encoding, following the fix for:

https://bugs.freepascal.org/view.php?id=30508

Basically, this is a Delphi compatibility fix.

This may impact some programs which use encodings that deviate from the
default system encoding.

In that case, the solution is to cast your string to RawByteString in the
constructor, or explicitly specify an encoding.

If you want to avoid encoding problems, using a TBytesStream may be a better
idea.

Michael.