Candidate for 0xc AngryBots

This is the same change as https://github.com/WebAssembly/webassembly.github.io/pull/14.

Note that it includes the changes described in WebAssembly/design#740
however it doesn't have any user-defined or names sections, so it's
unaffected by the details of how those are handled.

Author: sunfishcode

demo/AngryBots/AngryBots-0xc.wast.gz

@@ -97,11 +97,16 @@ function integrateWasmJS(Module) {
   };
   info["global.Math"] = global.Math;
   info["env"] = env;
-  var instance;
-  instance = Wasm.instantiateModule(binary, info).exports;
-  mergeMemory(instance.memory);
+  if (Wasm.experimentalVersion < 0xc || typeof WebAssembly == "undefined") {
+    var exports = Wasm.instantiateModule(binary, info).exports;
+    mergeMemory(exports.memory);
+    applyMappedGlobals();
+    return exports;
+  }
+  var exports = new WebAssembly.Instance(new WebAssembly.Module(binary), info).exports;
+  mergeMemory(exports.memory.buffer);
   applyMappedGlobals();
-  return instance;
+  return exports;
  });
 }
 Module["preRun"].push((function() {