SuperRegion doesn't call deallocate() on its PageReservation
https://bugs.webkit.org/show_bug.cgi?id=115208

Reviewed by Geoffrey Garen.

It should. This doesn't cause us to leak physical memory, but it does cause us to leak virtual
address space (and probably mach ports), which is also bad :-( FixedVMPoolExecutableAllocator
also has this bug, but it doesn't matter much because there's only one instance of that class
throughout the entire lifetime of the process, whereas each VM has its own SuperRegion.

* heap/SuperRegion.cpp:
(JSC::SuperRegion::~SuperRegion):
* heap/SuperRegion.h:
(SuperRegion):
* jit/ExecutableAllocatorFixedVMPool.cpp:
(FixedVMPoolExecutableAllocator):
(JSC::FixedVMPoolExecutableAllocator::~FixedVMPoolExecutableAllocator):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149165 268f45cc-cd09-0410-ab3c-d52691b4dbfc