[HTML5] Refactor JS, threads support, closures.

- Refactored the Engine code, splitted across files.
- Use MODULARIZE option to build emscripten code into it's own closure.
- Enable lto support (saves ~2MiB in release).
- Enable optional closure compiler pass for JS and generated code.
- Enable optional pthreads support.
- Can now build with tools=yes (not much to see yet).
- Dropped some deprecated code for older toolchains.

platform/javascript/engine/engine.js

@@ -0,0 +1,184 @@
+Function('return this')()['Engine'] = (function() {
+
+	var unloadAfterInit = true;
+	var canvas = null;
+	var resizeCanvasOnStart = false;
+	var customLocale = 'en_US';
+	var wasmExt = '.wasm';
+
+	var preloader = new Preloader();
+	var loader = new Loader();
+	var rtenv = null;
+
+	var executableName = '';
+	var loadPath = '';
+	var loadPromise = null;
+	var initPromise = null;
+	var stderr = null;
+	var stdout = null;
+	var progressFunc = null;
+
+	function load(basePath) {
+		if (loadPromise == null) {
+			loadPath = basePath;
+			loadPromise = preloader.loadPromise(basePath + wasmExt);
+			preloader.setProgressFunc(progressFunc);
+			requestAnimationFrame(preloader.animateProgress);
+		}
+		return loadPromise;
+	};
+
+	function unload() {
+		loadPromise = null;
+	};
+
+	/** @constructor */
+	function Engine() {};
+
+	Engine.prototype.init = /** @param {string=} basePath */ function(basePath) {
+		if (initPromise) {
+			return initPromise;
+		}
+		if (!loadPromise) {
+			if (!basePath) {
+				initPromise = Promise.reject(new Error("A base path must be provided when calling `init` and the engine is not loaded."));
+				return initPromise;
+			}
+			load(basePath);
+		}
+		var config = {}
+		if (typeof stdout === 'function')
+			config.print = stdout;
+		if (typeof stderr === 'function')
+			config.printErr = stderr;
+		initPromise = loader.init(loadPromise, loadPath, config).then(function() {
+			return new Promise(function(resolve, reject) {
+				rtenv = loader.env;
+				if (unloadAfterInit) {
+					loadPromise = null;
+				}
+				resolve();
+			});
+		});
+		return initPromise;
+	};
+
+	/** @type {function(string, string):Object} */
+	Engine.prototype.preloadFile = function(file, path) {
+		return preloader.preload(file, path);
+	};
+
+	/** @type {function(...string):Object} */
+	Engine.prototype.start = function() {
+		// Start from arguments.
+		var args = [];
+		for (var i = 0; i < arguments.length; i++) {
+			args.push(arguments[i]);
+		}
+		var me = this;
+		return new Promise(function(resolve, reject) {
+			return me.init().then(function() {
+				if (!(canvas instanceof HTMLCanvasElement)) {
+					canvas = Utils.findCanvas();
+				}
+				rtenv['locale'] = customLocale;
+				rtenv['canvas'] = canvas;
+				rtenv['thisProgram'] = executableName;
+				rtenv['resizeCanvasOnStart'] = resizeCanvasOnStart;
+				loader.start(preloader.preloadedFiles, args).then(function() {
+					loader = null;
+					initPromise = null;
+					resolve();
+				});
+			});
+		});
+	};
+
+	Engine.prototype.startGame = function(execName, mainPack) {
+		// Start and init with execName as loadPath if not inited.
+		executableName = execName;
+		var me = this;
+		return Promise.all([
+			this.init(execName),
+			this.preloadFile(mainPack, mainPack)
+		]).then(function() {
+			return me.start('--main-pack', mainPack);
+		});
+	};
+
+	Engine.prototype.setWebAssemblyFilenameExtension = function(override) {
+		if (String(override).length === 0) {
+			throw new Error('Invalid WebAssembly filename extension override');
+		}
+		wasmExt = String(override);
+	};
+
+	Engine.prototype.setUnloadAfterInit = function(enabled) {
+		unloadAfterInit = enabled;
+	};
+
+	Engine.prototype.setCanvas = function(canvasElem) {
+		canvas = canvasElem;
+	};
+
+	Engine.prototype.setCanvasResizedOnStart = function(enabled) {
+		resizeCanvasOnStart = enabled;
+	};
+
+	Engine.prototype.setLocale = function(locale) {
+		customLocale = locale;
+	};
+
+	Engine.prototype.setExecutableName = function(newName) {
+		executableName = newName;
+	};
+
+	Engine.prototype.setProgressFunc = function(func) {
+		progressFunc = func;
+	}
+
+	Engine.prototype.setStdoutFunc = function(func) {
+
+		var print = function(text) {
+			if (arguments.length > 1) {
+				text = Array.prototype.slice.call(arguments).join(" ");
+			}
+			func(text);
+		};
+		if (rtenv)
+			rtenv.print = print;
+		stdout = print;
+	};
+
+	Engine.prototype.setStderrFunc = function(func) {
+
+		var printErr = function(text) {
+			if (arguments.length > 1)
+				text = Array.prototype.slice.call(arguments).join(" ");
+			func(text);
+		};
+		if (rtenv)
+			rtenv.printErr = printErr;
+		stderr = printErr;
+	};
+
+	// Closure compiler exported engine methods.
+	/** @export */
+	Engine['isWebGLAvailable'] = Utils.isWebGLAvailable;
+	Engine['load'] = load;
+	Engine['unload'] = unload;
+	Engine.prototype['init'] = Engine.prototype.init
+	Engine.prototype['preloadFile'] = Engine.prototype.preloadFile
+	Engine.prototype['start'] = Engine.prototype.start
+	Engine.prototype['startGame'] = Engine.prototype.startGame
+	Engine.prototype['setWebAssemblyFilenameExtension'] = Engine.prototype.setWebAssemblyFilenameExtension
+	Engine.prototype['setUnloadAfterInit'] = Engine.prototype.setUnloadAfterInit
+	Engine.prototype['setCanvas'] = Engine.prototype.setCanvas
+	Engine.prototype['setCanvasResizedOnStart'] = Engine.prototype.setCanvasResizedOnStart
+	Engine.prototype['setLocale'] = Engine.prototype.setLocale
+	Engine.prototype['setExecutableName'] = Engine.prototype.setExecutableName
+	Engine.prototype['setProgressFunc'] = Engine.prototype.setProgressFunc
+	Engine.prototype['setStdoutFunc'] = Engine.prototype.setStdoutFunc
+	Engine.prototype['setStderrFunc'] = Engine.prototype.setStderrFunc
+	return Engine;
+})();