SpeculativeJIT should use OwnPtr<SlowPathGenerator>.
<http://webkit.org/b/111942>

Reviewed by Anders Carlsson.

There's no need to include DFGSlowPathGenerator.h from the header as long as the destructor is out-of-line,
so let's use OwnPtr instead of raw pointers + deleteAllValues().

* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::~SpeculativeJIT):
(JSC::DFG::SpeculativeJIT::addSlowPathGenerator):
* dfg/DFGSpeculativeJIT.h:
(SpeculativeJIT):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@145329 268f45cc-cd09-0410-ab3c-d52691b4dbfc