[wasm] GrowMemory should update imported memory objects.

src/wasm/wasm-js.cc

Index: src/wasm/wasm-js.cc
diff --git a/src/wasm/wasm-js.cc b/src/wasm/wasm-js.cc
index b5a3baf30b9b7d46dae5dc4896987754b27f8b29..62a4c5dfec1e22654afb993db3f69153ee0f9527 100644
--- a/src/wasm/wasm-js.cc
+++ b/src/wasm/wasm-js.cc
@@ -956,6 +956,12 @@ Handle<JSArrayBuffer> WasmJs::GetWasmMemoryArrayBuffer(Isolate* isolate,
   return Handle<JSArrayBuffer>::cast(buf);
 }
 
+void WasmJs::SetWasmMemoryArrayBuffer(Isolate* isolate, Handle<Object> value,
+                                      Handle<JSArrayBuffer> buffer) {
+  DCHECK(IsWasmMemoryObject(isolate, value));
+  JSObject::cast(*value)->SetInternalField(kWasmMemoryBuffer, *buffer);
+}
+
 uint32_t WasmJs::GetWasmMemoryMaximumSize(Isolate* isolate,
                                           Handle<Object> value) {
   DCHECK(IsWasmMemoryObject(isolate, value));