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

test/mjsunit/wasm/import-table.js

Index: test/mjsunit/wasm/import-table.js
diff --git a/test/mjsunit/wasm/import-table.js b/test/mjsunit/wasm/import-table.js
index ffb702c7817bc4bf6effe2a9c50f98e332b61073..ac27e519214726636dc1d30ce76cabdb2a5eef23 100644
--- a/test/mjsunit/wasm/import-table.js
+++ b/test/mjsunit/wasm/import-table.js
@@ -11,7 +11,7 @@ function testCallImport(func, check) {
   var builder = new WasmModuleBuilder();
 
   var sig_index = builder.addType(kSig_i_dd);
-  builder.addImport("func", sig_index);
+  builder.addImport("q", "func", sig_index);
   builder.addFunction("main", sig_index)
     .addBody([
       kExprGetLocal, 0,            // --
@@ -19,7 +19,7 @@ function testCallImport(func, check) {
       kExprCallFunction, 0])         // --
     .exportAs("main");
 
-  var main = builder.instantiate({func: func}).exports.main;
+  var main = builder.instantiate({q: {func: func}}).exports.main;
 
   for (var i = 0; i < 100000; i += 10003) {
     var a = 22.5 + i, b = 10.5 + i;
@@ -168,25 +168,23 @@ testCallImport(returnValue(objWithValueOf), checkReturn(198));
 
 
 function testCallBinopVoid(type, func, check) {
-  var ffi = new Object();
-
   var passed_length = -1;
   var passed_a = -1;
   var passed_b = -1;
   var args_a = -1;
   var args_b = -1;
 
-  ffi.func = function(a, b) {
+  var ffi = {q: {func: function(a, b) {
     passed_length = arguments.length;
     passed_a = a;
     passed_b = b;
     args_a = arguments[0];
     args_b = arguments[1];
-  }
+  }}};
 
   var builder = new WasmModuleBuilder();
 
-  builder.addImport("func", makeSig_v_xx(type));
+  builder.addImport("q", "func", makeSig_v_xx(type));
   builder.addFunction("main", makeSig_r_xx(kAstI32, type))
     .addBody([
       kExprGetLocal, 0,           // --
@@ -241,8 +239,8 @@ testCallBinopVoid(kAstF64);
 
 function testCallPrint() {
   var builder = new WasmModuleBuilder();
-  builder.addImport("print", makeSig_v_x(kAstI32));
-  builder.addImport("print", makeSig_r_x(kAstF64, kAstF64));
+  builder.addImport("q", "print", makeSig_v_x(kAstI32));
+  builder.addImport("q", "print", makeSig_r_x(kAstF64, kAstF64));
   builder.addFunction("main", makeSig_r_x(kAstF64, kAstF64))
     .addBody([
       kExprI8Const, 97,             // --
@@ -252,7 +250,7 @@ function testCallPrint() {
     ])
     .exportFunc();
 
-  var main = builder.instantiate({print: print}).exports.main;
+  var main = builder.instantiate({q: {print: print}}).exports.main;
 
   for (var i = -9; i < 900; i += 16.125) {
     main(i);
@@ -266,8 +264,8 @@ testCallPrint();
 function testCallImport2(foo, bar, expected) {
   var builder = new WasmModuleBuilder();
 
-  builder.addImport("foo", kSig_i_v);
-  builder.addImport("bar", kSig_i_v);
+  builder.addImport("q", "foo", kSig_i_v);
+  builder.addImport("t", "bar", kSig_i_v);
   builder.addFunction("main", kSig_i_v)
     .addBody([
       kExprCallFunction, 0, // --
@@ -276,7 +274,7 @@ function testCallImport2(foo, bar, expected) {
     ])                             // --
     .exportFunc();
 
-  var main = builder.instantiate({foo: foo, bar: bar}).exports.main;
+  var main = builder.instantiate({q: {foo: foo}, t: {bar: bar}}).exports.main;
   assertEquals(expected, main());
 }
 
@@ -285,7 +283,7 @@ testCallImport2(function() { return 33; }, function () { return 44; }, 77);
 
 function testImportName(name) {
   var builder = new WasmModuleBuilder();
-  builder.addImportWithModule("M", name, kSig_i_v);
+  builder.addImport("M", name, kSig_i_v);
   builder.addFunction("main", kSig_i_v)
     .addBody([
       kExprCallFunction, 0