Add support for parsing "refcounted" in classes.

pdecobj.pas:
  * parse_object_options: parse "refcounted" at the same position as "sealed" and "abstract"
  * parse_parent_classes: a class inherits the "oo_is_reference_counted" flag from its parent class
  * object_dec: if a class has "oo_is_reference_counted" set, then we add a hidden 32-bit signed integer field named "$refcount" if it is the first class in the hierarchy to have the flag (otherwise the field is "inherited" from its parent)


git-svn-id: http://svn.freepascal.org/svn/fpc/branches/svenbarth@28805 3ad0048d-3df7-0310-abae-a5850022a9f2
Correctly denote the Result symbol as "weak" if it was parsed as such.

pparautl.pas:
  * insert_funcret_para & insert_funcret_local: apply "vo_is_weakref" flag to the Result symbol if "retisweak" is set for the (abstract)procdef


git-svn-id: http://svn.freepascal.org/svn/fpc/branches/svenbarth@28806 3ad0048d-3df7-0310-abae-a5850022a9f2
"Self" variable is considered as "weak".

pparautl.pas, insert_self_and_vmt_para:
  * consider the Self value of method pointers as "weak"
  * consider the Self value for normal methods of a class as "weak"


git-svn-id: http://svn.freepascal.org/svn/fpc/branches/svenbarth@28807 3ad0048d-3df7-0310-abae-a5850022a9f2