Rename MovHint to MovHintEvent so I can create a NodeType called MovHint

Rubber stamped by Mark Hahnenberg.
        
This is similar to the SetLocal/SetLocalEvent naming scheme, where SetLocal is the
NodeType and SetLocalEvent is the VariableEventKind.

* dfg/DFGVariableEvent.cpp:
(JSC::DFG::VariableEvent::dump):
* dfg/DFGVariableEvent.h:
(JSC::DFG::VariableEvent::movHint):
(JSC::DFG::VariableEvent::id):
(JSC::DFG::VariableEvent::operand):
(VariableEvent):
* dfg/DFGVariableEventStream.cpp:
(JSC::DFG::VariableEventStream::reconstruct):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@144477 268f45cc-cd09-0410-ab3c-d52691b4dbfc