[wasm] Add tests for JS wrappers to test-run-wasm.

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.h"
 #include "src/api-natives.h"
 #include "src/assert-scope.h"
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/factory.h"
@@ skipping 289 matching lines @@
   Handle<JSFunction> function =
       ApiNatives::InstantiateFunction(temp).ToHandleChecked();
   PropertyAttributes attributes =
       static_cast<PropertyAttributes>(DONT_DELETE | READ_ONLY);
   JSObject::AddProperty(object, name, function, attributes);
 }
 
 
 void WasmJs::Install(Isolate* isolate, Handle<JSGlobalObject> global) {
   // Setup wasm function map.
-  Handle<Map> wasm_function_map = isolate->factory()->NewMap(
-      JS_FUNCTION_TYPE, JSFunction::kSize + kPointerSize);
-  wasm_function_map->set_is_callable();
-  global->native_context()->set_wasm_function_map(*wasm_function_map);
+  Handle<Context> context(global->native_context(), isolate);
+  InstallWasmFunctionMap(isolate, context);
 
   // Bind the WASM object.
   Factory* factory = isolate->factory();
   Handle<String> name = v8_str(isolate, "_WASMEXP_");
   Handle<JSFunction> cons = factory->NewFunction(name);
   JSFunction::SetInstancePrototype(
-      cons, Handle<Object>(global->native_context()->initial_object_prototype(),
-                           isolate));
+      cons, Handle<Object>(context->initial_object_prototype(), isolate));
   cons->shared()->set_instance_class_name(*name);
   Handle<JSObject> wasm_object = factory->NewJSObject(cons, TENURED);
   PropertyAttributes attributes = static_cast<PropertyAttributes>(DONT_ENUM);
   JSObject::AddProperty(global, name, wasm_object, attributes);
 
   // Install functions on the WASM object.
   InstallFunc(isolate, wasm_object, "instantiateModule", InstantiateModule);
   InstallFunc(isolate, wasm_object, "verifyModule", VerifyModule);
   InstallFunc(isolate, wasm_object, "verifyFunction", VerifyFunction);
   InstallFunc(isolate, wasm_object, "compileRun", CompileRun);
   InstallFunc(isolate, wasm_object, "asmCompileRun", AsmCompileRun);
   InstallFunc(isolate, wasm_object, "instantiateModuleFromAsm",
               InstantiateModuleFromAsm);
 }
+
+
+void WasmJs::InstallWasmFunctionMap(Isolate* isolate, Handle<Context> context) {
+  if (!context->get(Context::WASM_FUNCTION_MAP_INDEX)->IsMap()) {
+    Handle<Map> wasm_function_map = isolate->factory()->NewMap(
+        JS_FUNCTION_TYPE, JSFunction::kSize + kPointerSize);
+    wasm_function_map->set_is_callable();
+    context->set_wasm_function_map(*wasm_function_map);
+  }
+}
+
 }  // namespace internal
 }  // namespace v8