[ignition] Reuse code-stub-assembler's context load operations.

src/interpreter/interpreter.cc

Index: src/interpreter/interpreter.cc
diff --git a/src/interpreter/interpreter.cc b/src/interpreter/interpreter.cc
index d36480769b0d296ec5891ce895805854c78b8b03..ae7c2a911dfa0ed58e18b9c0d49b39432f58d15b 100644
--- a/src/interpreter/interpreter.cc
+++ b/src/interpreter/interpreter.cc
@@ -497,9 +497,9 @@ void Interpreter::DoStaGlobal(Callable ic, InterpreterAssembler* assembler) {
   typedef StoreWithVectorDescriptor Descriptor;
   // Get the global object.
   Node* context = __ GetContext();
-  Node* native_context =
-      __ LoadContextSlot(context, Context::NATIVE_CONTEXT_INDEX);
-  Node* global = __ LoadContextSlot(native_context, Context::EXTENSION_INDEX);
+  Node* native_context = __ LoadNativeContext(context);
+  Node* global =
+      __ LoadContextElement(native_context, Context::EXTENSION_INDEX);
 
   // Store the global via the StoreIC.
   Node* code_target = __ HeapConstant(ic.code());
@@ -1757,8 +1757,7 @@ void Interpreter::DoCallJSRuntime(InterpreterAssembler* assembler) {
 
   // Get the function to call from the native context.
   Node* context = __ GetContext();
-  Node* native_context =
-      __ LoadContextSlot(context, Context::NATIVE_CONTEXT_INDEX);
+  Node* native_context = __ LoadNativeContext(context);
   Node* function = __ LoadContextSlot(native_context, context_index);
 
   // Call the function.