[Lazarus] [lazarus] Patch for processing WM_COPYDATA in Win32 / BugID 9210

[Felipe Monteiro de Carvalho]

In the past I thougth that using SetWindowLong was hard. It isn't. It
will return the address of the current WndProc, so you can just have
your WndProc like this:

begin
  if Msg = WM_COPYDATA then
 ...
  else CallOldWindowProc;
end;

And you don't lose anything. With a clever code you can even use the
same wndproc for any control, just take care to call the correct old
wndproc in each case.

-- 
Felipe Monteiro de Carvalho