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

test/mjsunit/wasm/exceptions.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 --wasm-eh-prototype
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
 // The following methods do not attempt to catch the exception they raise.
@@ skipping 61 matching lines @@
 // Now that we know throwing works, we test catching the exceptions we raise.
 var test_catch = (function () {
   var builder = new WasmModuleBuilder();
 
     // Helper function for throwing from js. It is imported by the Wasm module
     // as throw_i.
     function throw_value(value) {
       throw value;
     }
     var sig_index = builder.addType(kSig_v_i);
-    var kJSThrowI = builder.addImport("throw_i", sig_index);
+    var kJSThrowI = builder.addImport("", "throw_i", sig_index);
 
     // Helper function that throws a string. Wasm should not catch it.
     function throw_string() {
       throw "use wasm;";
     }
     sig_index = builder.addType(kSig_v_v);
-    var kJSThrowString = builder.addImport("throw_string", sig_index);
+    var kJSThrowString = builder.addImport("", "throw_string", sig_index);
 
     // Helper function that throws undefined. Wasm should not catch it.
     function throw_undefined() {
       throw undefined;
     }
-    var kJSThrowUndefined = builder.addImport("throw_undefined", sig_index);
+    var kJSThrowUndefined = builder.addImport("", "throw_undefined", sig_index);
 
     // Helper function that throws an fp. Wasm should not catch it.
     function throw_fp() {
       throw 10.5;
     }
-    var kJSThrowFP = builder.addImport("throw_fp", sig_index);
+    var kJSThrowFP = builder.addImport("", "throw_fp", sig_index);
 
     // Helper function that throws a large number. Wasm should not catch it.
     function throw_large() {
       throw 1e+28;
     }
-    var kJSThrowLarge = builder.addImport("throw_large", sig_index);
+    var kJSThrowLarge = builder.addImport("", "throw_large", sig_index);
 
     // Helper function for throwing from WebAssembly.
     var kWasmThrowFunction =
       builder.addFunction("throw", kSig_v_i)
         .addBody([
           kExprGetLocal, 0,
           kExprThrow
         ])
         .index;
 
@@ skipping 210 matching lines @@
           kExprCallFunction, kJSThrowLarge
       ])
       .exportFunc();
 
     builder.addFunction("undefined_from_js", kSig_v_v)
       .addBody([
           kExprCallFunction, kJSThrowUndefined
       ])
       .exportFunc();
 
-  return builder.instantiate({
+  return builder.instantiate({"": {
       throw_i: throw_value,
       throw_string: throw_string,
       throw_fp: throw_fp,
       throw_large, throw_large,
       throw_undefined: throw_undefined
-  });
+  }});
 })();
 
 // Check the test_catch exists.
 assertFalse(test_catch === undefined);
 assertFalse(test_catch === null);
 assertFalse(test_catch === 0);
 assertEquals("object", typeof test_catch.exports);
 assertEquals("function", typeof test_catch.exports.same_scope);
 assertEquals("function", typeof test_catch.exports.same_scope_ignore);
 assertEquals("function", typeof test_catch.exports.same_scope_multiple);
@@ skipping 19 matching lines @@
 assertEquals(-1, test_catch.exports.from_direct_callee(0xFFFFFFFF));
 assertEquals(0x7FFFFFFF, test_catch.exports.from_direct_callee(0x7FFFFFFF));
 assertEquals(-10, test_catch.exports.from_indirect_callee(10));
 assertEquals(-77, test_catch.exports.from_indirect_callee(77));
 assertEquals(10, test_catch.exports.from_js(10));
 assertEquals(-10, test_catch.exports.from_js(-10));
 
 assertThrowsEquals(test_catch.exports.string_from_js, "use wasm;");
 assertThrowsEquals(test_catch.exports.large_from_js, 1e+28);
 assertThrowsEquals(test_catch.exports.undefined_from_js, undefined);