Add offenders to imageOptimization

lib/tools/weightChecker/imageOptimizer.js

@@ -149,10 +149,12 @@ var ImageOptimizer = function() {
         return deferred.promise;
     }
 
+    // The gain is estimated of enough value if it's over 2KB or over 20%,
+    // but it's ignored if is below 100 bytes
     function gainIsEnough(oldWeight, newWeight) {
         var gain = oldWeight - newWeight;
         var ratio = gain / oldWeight;
-        return (gain > 2048 || ratio > 0.2);
+        return (gain > 2048 || (ratio > 0.2 && gain > 100));
     }
 
     function isJpeg(entry) {

lib/tools/weightChecker/weightChecker.js

@@ -140,45 +140,16 @@ var WeightChecker = function() {
     function listImageNotOptimized(requests) {
         var results = {
             totalGain: 0,
-            byType: {
-                jpeg: {
-                    totalGain: 0,
-                    requests: []
-                },
-                png: {
-                    totalGain: 0,
-                    requests: []
-                },
-                svg: {
-                    totalGain: 0,
-                    requests: []
-                }
-            }
+            images: []
         };
 
         requests.forEach(function(req) {
-            var type = null;
-
-            switch(req.contentType) {
-                case 'image/jpeg':
-                    type = 'jpeg';
-                    break;
-                case 'image/png':
-                    type = 'png';
-                    break;
-                case 'image/svg+xml':
-                    type = 'svg';
-                    break;
-            }
-
-            if (type && req.weightCheck.bodySize && req.weightCheck.isOptimized === false) {
+            if (req.weightCheck.bodySize && req.weightCheck.isOptimized === false) {
                 var gain = req.weightCheck.bodySize - req.weightCheck.optimized;
 
                 results.totalGain += gain;
 
-                results.byType[type].totalGain += gain;
-
-                results.byType[type].requests.push({
+                results.images.push({
                     url: req.url,
                     original: req.weightCheck.bodySize,
                     optimized: req.weightCheck.optimized,