[wasm] Detach memory buffer only when GrowMemory is called from the JS API

src/wasm/wasm-js.cc

 // 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.
 
 #include "src/api-natives.h"
 #include "src/api.h"
 #include "src/asmjs/asm-js.h"
 #include "src/asmjs/asm-typer.h"
 #include "src/asmjs/asm-wasm-builder.h"
 #include "src/assert-scope.h"
@@ skipping 680 matching lines @@
     thrower.RangeError(new_size64 < old_size ? "trying to shrink memory"
                                              : "maximum memory size exceeded");
     return;
   }
   int32_t ret = i::wasm::GrowWebAssemblyMemory(
       i_isolate, receiver, static_cast<uint32_t>(delta_size));
   if (ret == -1) {
     thrower.RangeError("Unable to grow instance memory.");
     return;
   }
+  i::wasm::DetachWebAssemblyMemoryBuffer(i_isolate, old_buffer);
   v8::ReturnValue<v8::Value> return_value = args.GetReturnValue();
   return_value.Set(ret);
 }
 
 // WebAssembly.Memory.buffer -> ArrayBuffer
 void WebAssemblyMemoryGetBuffer(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::Isolate* isolate = args.GetIsolate();
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
   HandleScope scope(isolate);
@@ skipping 213 matching lines @@
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_memory_sym(), isolate);
   return HasBrand(value, symbol);
 }
 
 bool WasmJs::IsWasmTableObject(Isolate* isolate, Handle<Object> value) {
   i::Handle<i::Symbol> symbol(isolate->context()->wasm_table_sym(), isolate);
   return HasBrand(value, symbol);
 }
 }  // namespace internal
 }  // namespace v8