[wasm] Remove two obsolete functions

src/wasm/wasm-objects.h

Index: src/wasm/wasm-objects.h
diff --git a/src/wasm/wasm-objects.h b/src/wasm/wasm-objects.h
index 1b1dca53ab7b12e57ae999bfdef06b1278ae777c..b0de953203b42bc11dbd2094e84faf2801cebee3 100644
--- a/src/wasm/wasm-objects.h
+++ b/src/wasm/wasm-objects.h
@@ -275,12 +275,12 @@ class WasmDebugInfo : public FixedArray {
  public:
   enum class Fields { kFieldCount };
 
-  static Handle<WasmDebugInfo> New(Handle<JSObject> wasm);
+  static Handle<WasmDebugInfo> New(Handle<WasmInstanceObject> instance);
 
   static bool IsDebugInfo(Object* object);
   static WasmDebugInfo* cast(Object* object);
 
-  JSObject* wasm_instance();
+  WasmInstanceObject* wasm_instance();
 
   bool SetBreakPoint(int byte_offset);