Remove CSS Modules postcss plugins in Global mode

Fixes webpack-contrib#308

Author: geelen

lib/processCss.js

@@ -147,33 +147,40 @@ module.exports = function processCss(inputSource, inputMap, options, callback) {
 		import: query.import !== false
 	};
 
-	var pipeline = postcss([
-		localByDefault({
-			mode: options.mode,
-			rewriteUrl: function(global, url) {
-				if(parserOptions.url){
-					if(!loaderUtils.isUrlRequest(url, root)) {
-						return url;
-					}
-					if(global) {
-						return loaderUtils.urlToRequest(url, root);
+	var pipeline = postcss(
+		(options.mode === 'local' ? [
+			/* LOCAL ONLY POSTCSS PLUGINS */
+			localByDefault({
+				mode: options.mode,
+				rewriteUrl: function(global, url) {
+					if(parserOptions.url){
+						if(!loaderUtils.isUrlRequest(url, root)) {
+							return url;
+						}
+						if(global) {
+							return loaderUtils.urlToRequest(url, root);
+						}
 					}
+					return url;
 				}
-				return url;
-			}
-		}),
-		extractImports(),
-		modulesValues,
-		modulesScope({
-			generateScopedName: function(exportName) {
-				return getLocalIdent(options.loaderContext, localIdentName, exportName, {
-					regExp: localIdentRegExp,
-					hashPrefix: query.hashPrefix || "",
-					context: context
-				});
-			}
-		}),
-		parserPlugin(parserOptions)
+			}),
+			extractImports(),
+			modulesValues,
+			modulesScope({
+				generateScopedName: function(exportName) {
+					return getLocalIdent(options.loaderContext, localIdentName, exportName, {
+						regExp: localIdentRegExp,
+						hashPrefix: query.hashPrefix || "",
+						context: context
+					});
+				}
+			})
+		] : [
+			/* GLOBAL ONLY POSTCSS PLUGINS */
+		]).concat([
+			/* COMMON POSTCSS PLUGINS */
+			parserPlugin(parserOptions)
+		])
 	]);
 
 	if(minimize) {