Remove new redundant options arg from algorithm

It was introduced in 0.3.1 and broke configurations passing an explicit
algorithm function, as the signature used to be function(buff, cb).

Author: h4l

index.js

@@ -11,30 +11,29 @@ function CompressionPlugin(options) {
 	options = options || {};
 	this.asset = options.asset || "[path].gz[query]";
 	this.algorithm = options.algorithm || "gzip";
-	this.compressionOptions = {};
 	if(typeof this.algorithm === "string") {
 		if (this.algorithm === "zopfli") {
 			try {
 				var zopfli = require("node-zopfli");
 			} catch(err) {
 				throw new Error("node-zopfli not found");
 			}
-			this.compressionOptions = {
+			var compressionOptions = {
 				verbose: options.hasOwnProperty('verbose') ? options.verbose : false,
 				verbose_more: options.hasOwnProperty('verbose_more') ? options.verbose_more : false,
 				numiterations: options.numiterations ? options.numiterations : 15,
 				blocksplitting: options.hasOwnProperty('blocksplitting') ? options.blocksplitting : true,
 				blocksplittinglast: options.hasOwnProperty('blocksplittinglast') ? options.blocksplittinglast : false,
 				blocksplittingmax: options.blocksplittingmax ? options.blocksplittingmax : 15
 			};
-			this.algorithm = function (content, options, fn) {
-				zopfli.gzip(content, options, fn);
+			this.algorithm = function (content, fn) {
+				zopfli.gzip(content, compressionOptions, fn);
 			};
 		} else {
 			var zlib = require("zlib");
-			this.algorithm = zlib[this.algorithm];
+			var algorithm = zlib[this.algorithm];
 			if(!this.algorithm) throw new Error("Algorithm not found in zlib");
-			this.compressionOptions = {
+			var compressionOptions = {
 				level: options.level || 9,
 				flush: options.flush,
 				chunkSize: options.chunkSize,
@@ -43,6 +42,9 @@ function CompressionPlugin(options) {
 				strategy: options.strategy,
 				dictionary: options.dictionary
 			};
+			this.algorithm = function(content, fn) {
+				algorithm(content, compressionOptions, fn);
+			};
 		}
 	}
 	this.test = options.test || options.regExp;
@@ -67,7 +69,7 @@ CompressionPlugin.prototype.apply = function(compiler) {
 					content = new Buffer(content, "utf-8");
 				var originalSize = content.length;
 				if(originalSize < this.threshold) return callback();
-				this.algorithm(content, this.compressionOptions, function(err, result) {
+				this.algorithm(content, function(err, result) {
 					if(err) return callback(err);
 					if(result.length / originalSize > this.minRatio) return callback();
 					var parse = url.parse(file);