Make about:net-internal's filters work a bit better.

chrome/browser/resources/net_internals/events_view.js

Index: chrome/browser/resources/net_internals/events_view.js
===================================================================
--- chrome/browser/resources/net_internals/events_view.js	(revision 158398)
+++ chrome/browser/resources/net_internals/events_view.js	(working copy)
@@ -285,9 +285,23 @@
           var filterInfo = this.parseDirective_(filterText, directive);
           if (filterInfo == null)
             break;
-          if (!filter[directive])
-            filter[directive] = [];
-          filter[directive].push(filterInfo.parameter);
+
+          // Split parameters around commas and remove empty elements.
+          var parameters = filterInfo.parameter.split(',');
+          parameters = parameters.filter(function(string) {
+              return string.length > 0;
+          });
+
+          // If there's already a matching filter, take the intersection.
+          // This behavior primarily exists for tests.  It is not correct
+          // when one of the 'type' filters is a partial match.
+          if (filter[directive]) {
+            parameters = parameters.filter(function(string) {
+                return filter[directive].indexOf(string) != -1;
+            });
+          }
+
+          filter[directive] = parameters;
           filterText = filterInfo.remainingText;
         }
       }