[turbofan] Context specialization should only specialize loads/stores.

src/compiler/js-context-specialization.h

Index: src/compiler/js-context-specialization.h
diff --git a/src/compiler/js-context-specialization.h b/src/compiler/js-context-specialization.h
index 2ede6b5e1767f163396c057fc5fbe6ad1061d7ad..ef784fc442812ca1c9a7cac1622a4c194a389786 100644
--- a/src/compiler/js-context-specialization.h
+++ b/src/compiler/js-context-specialization.h
@@ -27,10 +27,12 @@ class JSContextSpecialization final : public AdvancedReducer {
   Reduction Reduce(Node* node) final;
 
  private:
-  Reduction ReduceParameter(Node* node);
   Reduction ReduceJSLoadContext(Node* node);
   Reduction ReduceJSStoreContext(Node* node);
 
+  // Returns the {Context} to specialize {node} to (if any).
+  MaybeHandle<Context> GetSpecializationContext(Node* node);
+
   Isolate* isolate() const;
   JSOperatorBuilder* javascript() const;
   JSGraph* jsgraph() const { return jsgraph_; }