[wasm] Implement correct 2-level namespace for imports.

test/mjsunit/wasm/compiled-module-management.js

 // Copyright 2016 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.
 
 // Flags: --expose-wasm --expose-gc --allow-natives-syntax
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 // Use global variables for all values where the test wants to maintain strict
 // control over value lifetime. Using local variables would not give sufficient
 // guarantees of the value lifetime.
 var module;
 var instance1;
 var instance2;
 var instance3;
 var instance4;
 
 (function CompiledModuleInstancesInitialize1to3() {
   var builder = new WasmModuleBuilder();
 
   builder.addMemory(1,1, true);
-  builder.addImport("getValue", kSig_i_v);
+  builder.addImport("", "getValue", kSig_i_v);
   builder.addFunction("f", kSig_i_v)
     .addBody([
       kExprCallFunction, 0
     ]).exportFunc();
 
   module = new WebAssembly.Module(builder.toBuffer());
   %ValidateWasmModuleState(module);
   %ValidateWasmInstancesChain(module, 0);
-  instance1 = new WebAssembly.Instance(module, {getValue: () => 1});
+  instance1 = new WebAssembly.Instance(module, {"": {getValue: () => 1}});
   %ValidateWasmInstancesChain(module, 1);
-  instance2 = new WebAssembly.Instance(module, {getValue: () => 2});
+  instance2 = new WebAssembly.Instance(module, {"": {getValue: () => 2}});
   %ValidateWasmInstancesChain(module, 2);
-  instance3 = new WebAssembly.Instance(module, {getValue: () => 3});
+  instance3 = new WebAssembly.Instance(module, {"": {getValue: () => 3}});
   %ValidateWasmInstancesChain(module, 3);
 })();
 
 (function CompiledModuleInstancesClear1() {
   assertEquals(1, instance1.exports.f());
   instance1 = null;
 })();
 
 gc();
 %ValidateWasmInstancesChain(module, 2);
 
 (function CompiledModuleInstancesClear3() {
   assertEquals(3, instance3.exports.f());
   instance3 = null;
 })();
 
 gc();
 %ValidateWasmInstancesChain(module, 1);
 
 (function CompiledModuleInstancesClear2() {
   assertEquals(2, instance2.exports.f());
   instance2 = null;
 })();
 
 gc();
 %ValidateWasmModuleState(module);
 
 (function CompiledModuleInstancesInitialize4AndClearModule() {
-  instance4 = new WebAssembly.Instance(module, {getValue: () => 4});
+  instance4 = new WebAssembly.Instance(module, {"": {getValue: () => 4}});
   assertEquals(4, instance4.exports.f());
   module = null;
 })();
 
 gc();
 %ValidateWasmOrphanedInstance(instance4);