[webpack-contrib#39] Don't use styleSheet to store state of css text

IE9 will actually drop certain things (like media queries) from the
cssText property when it is read back out. To fix, store the raw css
text in a separately managed array, and use that to form the entire
string that should be set on the style element's cssText property.

Fixes webpack-contrib#39.

Author: diurnalist

addStyles.js

@@ -153,25 +153,20 @@ function addStyle(obj, options) {
 	};
 }
 
-function replaceText(source, id, replacement) {
-	var boundaries = ["/** >>" + id + " **/", "/** " + id + "<< **/"];
-	var start = source.lastIndexOf(boundaries[0]);
-	var wrappedReplacement = replacement
-		? (boundaries[0] + replacement + boundaries[1])
-		: "";
-	if (source.lastIndexOf(boundaries[0]) >= 0) {
-		var end = source.lastIndexOf(boundaries[1]) + boundaries[1].length;
-		return source.slice(0, start) + wrappedReplacement + source.slice(end);
-	} else {
-		return source + wrappedReplacement;
-	}
-}
+var replaceText = (function () {
+	var textStore = [];
+
+	return function (index, replacement) {
+		textStore[index] = replacement;
+		return textStore.filter(Boolean).join('\n');
+	};
+})();
 
 function applyToSingletonTag(styleElement, index, remove, obj) {
 	var css = remove ? "" : obj.css;
 
-	if(styleElement.styleSheet) {
-		styleElement.styleSheet.cssText = replaceText(styleElement.styleSheet.cssText, index, css);
+	if (styleElement.styleSheet) {
+		styleElement.styleSheet.cssText = replaceText(index, css);
 	} else {
 		var cssNode = document.createTextNode(css);
 		var childNodes = styleElement.childNodes;