[wasm] Instance exports object should be iterable

test/mjsunit/wasm/instantiate-module-basic.js

 // 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.
 
 // Flags: --expose-wasm
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 let kReturnValue = 17;
@@ skipping 229 matching lines @@
 
 
   assertThrows(() => new WebAssembly.Instance(module, {"":{memory:memory}}), WebAssembly.LinkError);
 })();
 
 (function TestNoMemoryToExport() {
   let builder = new WasmModuleBuilder();
   builder.exportMemoryAs('memory');
   assertThrows(() => builder.instantiate(), WebAssembly.CompileError);
 })();
+
+(function TestIterableExports() {
+  print("TestIterableExports...");
+  let builder = new WasmModuleBuilder;
+  builder.addExport("a", builder.addFunction("", kSig_v_v).addBody([]));
+  builder.addExport("b", builder.addFunction("", kSig_v_v).addBody([]));
+  builder.addExport("c", builder.addFunction("", kSig_v_v).addBody([]));
+  builder.addExport("d", builder.addFunction("", kSig_v_v).addBody([]));
+  builder.addExport("e", builder.addGlobal(kWasmI32, false));
+
+  let module = new WebAssembly.Module(builder.toBuffer());
+  let instance = new WebAssembly.Instance(module);
+
+  let exports_count = 0;
+  for (var e in instance.exports) ++exports_count;
+
+  assertEquals(5, exports_count);
+})();