add some packages

node_modules/clean-css/lib/optimizer/level-2/remove-duplicate-media-queries.js

@@ -0,0 +1,30 @@
+var Token = require('../../tokenizer/token');
+
+var serializeAll = require('../../writer/one-time').all;
+var serializeRules = require('../../writer/one-time').rules;
+
+function removeDuplicateMediaQueries(tokens) {
+  var candidates = {};
+  var candidate;
+  var token;
+  var key;
+  var i, l;
+
+  for (i = 0, l = tokens.length; i < l; i++) {
+    token = tokens[i];
+    if (token[0] != Token.NESTED_BLOCK) {
+      continue;
+    }
+
+    key = serializeRules(token[1]) + '%' + serializeAll(token[2]);
+    candidate = candidates[key];
+
+    if (candidate) {
+      candidate[2] = [];
+    }
+
+    candidates[key] = token;
+  }
+}
+
+module.exports = removeDuplicateMediaQueries;