[wasm] remove unused WasmInstance fields

src/wasm/wasm-module.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_WASM_MODULE_H_
 #define V8_WASM_MODULE_H_
 
 #include <memory>
 
 #include "src/api.h"
@@ skipping 214 matching lines @@
       Handle<Script> asm_js_script,
       Vector<const byte> asm_js_offset_table_bytes) const;
 };
 
 typedef Managed<WasmModule> WasmModuleWrapper;
 
 // An instantiated WASM module, including memory, function table, etc.
 struct WasmInstance {
   const WasmModule* module;  // static representation of the module.
   // -- Heap allocated --------------------------------------------------------
-  Handle<JSObject> js_object;            // JavaScript module object.
   Handle<Context> context;               // JavaScript native context.
-  Handle<JSArrayBuffer> mem_buffer;      // Handle to array buffer of memory.
-  Handle<JSArrayBuffer> globals_buffer;  // Handle to array buffer of globals.
   std::vector<Handle<FixedArray>> function_tables;  // indirect function tables.
   std::vector<Handle<Code>> function_code;  // code objects for each function.
   // -- raw memory ------------------------------------------------------------
   byte* mem_start = nullptr;  // start of linear memory.
   uint32_t mem_size = 0;      // size of the linear memory.
   // -- raw globals -----------------------------------------------------------
   byte* globals_start = nullptr;  // start of the globals area.
 
   explicit WasmInstance(const WasmModule* m)
       : module(m),
@@ skipping 190 matching lines @@
 void ValidateModuleState(Isolate* isolate, Handle<WasmModuleObject> module_obj);
 void ValidateOrphanedInstance(Isolate* isolate,
                               Handle<WasmInstanceObject> instance);
 
 }  // namespace testing
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_MODULE_H_