[turbofan] Use InternalizedString feedback abstract/strict equality comparisons.

src/compiler/simplified-lowering.cc

Index: src/compiler/simplified-lowering.cc
diff --git a/src/compiler/simplified-lowering.cc b/src/compiler/simplified-lowering.cc
index f38401b09c923175c9c7b45e910f19224e195da4..be7fda558ca2324ef73d5f636ffb1cfcbfd38244 100644
--- a/src/compiler/simplified-lowering.cc
+++ b/src/compiler/simplified-lowering.cc
@@ -2253,6 +2253,17 @@ class RepresentationSelector {
         SetOutput(node, MachineRepresentation::kNone);
         return;
       }
+      case IrOpcode::kCheckInternalizedString: {
+        if (InputIs(node, Type::InternalizedString())) {
+          VisitUnop(node, UseInfo::AnyTagged(),
+                    MachineRepresentation::kTaggedPointer);
+          if (lower()) DeferReplacement(node, node->InputAt(0));
+        } else {
+          VisitUnop(node, UseInfo::AnyTagged(),
+                    MachineRepresentation::kTaggedPointer);
+        }
+        return;
+      }
       case IrOpcode::kCheckNumber: {
         if (InputIs(node, Type::Number())) {
           if (truncation.IsUsedAsWord32()) {