add_mapping_callback on Darwin: also produce a ChangedSeg record in
the case where V's record of the permissions for a range differs from
that of the kernel's.  The lack of this caused synthetic segfaults
("can't translate here") from m_translate on OSX 10.8 for pretty much
any graphical .



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13522 a5019735-40e9-0310-863c-91ae7b9d1cf9
Make wqthread_hijack work with the OSX 10.8 kernel.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13523 a5019735-40e9-0310-863c-91ae7b9d1cf9
Fixes and kludges (mostly the latter) needed to	run graphical
apps on	  OSX 10.8:

* port_create_vanilla: deal with the fact that ports get looked
  up before they get registered in the allocated_ports list.  I
  think this is	 a side effect of ..

* .. various syscalls: add stub (no-op) wrappers



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13524 a5019735-40e9-0310-863c-91ae7b9d1cf9