[wasm] Names of exported functions should be the stringified function index.

test/mjsunit/wasm/function-prototype.js

Index: test/mjsunit/wasm/function-prototype.js
diff --git a/test/mjsunit/wasm/function-prototype.js b/test/mjsunit/wasm/function-prototype.js
index fdf788f773493c8f7f26f1093bb91e3495dbe80c..f2361039c9cc2f97b4cbc09ff7bca6cffc0c5dde 100644
--- a/test/mjsunit/wasm/function-prototype.js
+++ b/test/mjsunit/wasm/function-prototype.js
@@ -10,7 +10,7 @@ load("test/mjsunit/wasm/wasm-module-builder.js");
 (function TestFunctionPrototype() {
   var builder = new WasmModuleBuilder();
 
-  builder.addFunction("nine", kSig_i_v)
+  var f = builder.addFunction("nine", kSig_i_v)
     .addBody([kExprI8Const, 9])
     .exportFunc();
 
@@ -19,7 +19,7 @@ load("test/mjsunit/wasm/wasm-module-builder.js");
   // Check type and existence of prototype
   assertEquals("function", typeof func.apply);
   assertTrue(func.prototype != undefined);
-  assertEquals("nine", func.name);
+  assertEquals(String(f.index), func.name);
   assertEquals(undefined, func.displayName);
 
   // Check that .apply() works.