[turbofan] Move graph trimming functionality to dedicated GraphTrimmer.

src/compiler/node-marker.cc

Index: src/compiler/node-marker.cc
diff --git a/src/compiler/node-marker.cc b/src/compiler/node-marker.cc
index 3e56a11271a3ec0120ea820a7f1b0751ae47f269..fdfb22b21a58560f4efcbbc7bbdd2239daa7f527 100644
--- a/src/compiler/node-marker.cc
+++ b/src/compiler/node-marker.cc
@@ -16,14 +16,6 @@ NodeMarkerBase::NodeMarkerBase(Graph* graph, uint32_t num_states)
   DCHECK_LT(mark_min_, mark_max_);  // check for wraparound.
 }
 
-
-void NodeMarkerBase::Reset(Graph* graph) {
-  uint32_t const num_states = mark_max_ - mark_min_;
-  mark_min_ = graph->mark_max_;
-  mark_max_ = graph->mark_max_ += num_states;
-  DCHECK_LT(mark_min_, mark_max_);  // check for wraparound.
-}
-
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8