Caused a 5% sunspider regression in-browser.

Unreviewed rollout.

* bytecode/CodeBlock.cpp:
(JSC::CodeBlock::visitAggregate):
* heap/Heap.cpp:
(JSC::Heap::collectAllGarbage):
* heap/MarkStack.h:
(JSC::MarkStack::MarkStack):
* runtime/JSGlobalData.cpp:
(JSC::JSGlobalData::releaseExecutableMemory):
* runtime/RegExp.cpp:
(JSC::RegExp::compile):
(JSC::RegExp::invalidateCode):
* runtime/RegExp.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@91869 268f45cc-cd09-0410-ab3c-d52691b4dbfc