EmscriptenApplication: use existing Module object

This prevents deleting elements in Module that were set by Emscripten preamble code when using EmscriptenApplication.js with --pre-js

src/Magnum/Platform/EmscriptenApplication.js

@@ -25,46 +25,47 @@
 
 "use strict"; /* it summons the Cthulhu in a proper way, they say */
 
-var Module = {
-    preRun: [],
-    postRun: [],
+var Module = typeof Module !== "undefined" ? Module : {};
 
-    arguments: [],
+Module.preRun = [];
+Module.postRun = [];
 
-    printErr: function(message) {
+Module.arguments = [];
+
+Module.printErr = function(_message) {
     console.error(Array.prototype.slice.call(arguments).join(' '));
-    },
+};
 
-    print: function(message) {
+Module.print = function(_message) {
     console.log(Array.prototype.slice.call(arguments).join(' '));
-    },
+};
 
-    onAbort: function() {
+Module.onAbort = function() {
     Module.canvas.style.opacity = 0.333;
     Module.canvas.style.zIndex = -1;
     Module.setStatus("Oops :(");
     Module.setStatusDescription("The app crashed. Refresh the page or check the browser console for details.");
-    },
+};
 
-    canvas: document.getElementById('canvas'),
-    status: document.getElementById('status'),
-    statusDescription: document.getElementById('status-description'),
+Module.canvas = document.getElementById('canvas');
+Module.status = document.getElementById('status');
+Module.statusDescription = document.getElementById('status-description');
 
-    setStatus: function(message) {
+Module.setStatus = function(message) {
     /* Emscripten calls setStatus("") after a timeout even if the app
         aborts. That would erase the crash message, so don't allow that */
     if(Module.status && Module.status.innerHTML != "Oops :(")
         Module.status.innerHTML = message;
-    },
+};
 
-    setStatusDescription: function(message) {
+Module.setStatusDescription = function(message) {
     if(Module.statusDescription)
         Module.statusDescription.innerHTML = message;
-    },
+};
 
-    totalDependencies: 0,
+Module.totalDependencies = 0;
 
-    monitorRunDependencies: function(left) {
+Module.monitorRunDependencies = function(left) {
     this.totalDependencies = Math.max(this.totalDependencies, left);
 
     if(left) {
@@ -74,7 +75,6 @@ var Module = {
         Module.setStatus('Download complete');
         Module.setStatusDescription('');
     }
-    }
 };
 
 /* Parse arguments, e.g. /app/?foo=bar&fizz&buzz=3 goes to the app as