[turbofan] Move lowering of ObjectIs* nodes to ChangeLowering.

src/compiler/simplified-lowering.h

Index: src/compiler/simplified-lowering.h
diff --git a/src/compiler/simplified-lowering.h b/src/compiler/simplified-lowering.h
index 0fb079d38c6ff967ca3a4a86ffd7331fd03105f8..6792045d7bffe0ce5a88324c870abbab772a003e 100644
--- a/src/compiler/simplified-lowering.h
+++ b/src/compiler/simplified-lowering.h
@@ -36,9 +36,6 @@ class SimplifiedLowering final {
   void DoLoadBuffer(Node* node, MachineRepresentation rep,
                     RepresentationChanger* changer);
   void DoStoreBuffer(Node* node);
-  void DoObjectIsNumber(Node* node);
-  void DoObjectIsReceiver(Node* node);
-  void DoObjectIsSmi(Node* node);
   void DoShift(Node* node, Operator const* op, Type* rhs_type);
   void DoStringEqual(Node* node);
   void DoStringLessThan(Node* node);
@@ -56,9 +53,6 @@ class SimplifiedLowering final {
   // position information via the SourcePositionWrapper like all other reducers.
   SourcePositionTable* source_positions_;
 
-  Node* IsSmi(Node* value);
-  Node* LoadHeapObjectMap(Node* object, Node* control);
-  Node* LoadMapInstanceType(Node* map);
   Node* StringComparison(Node* node);
   Node* Int32Div(Node* const node);
   Node* Int32Mod(Node* const node);