Trace category groups and category filter.

chrome/browser/ui/webui/tracing_ui.cc

Index: chrome/browser/ui/webui/tracing_ui.cc
diff --git a/chrome/browser/ui/webui/tracing_ui.cc b/chrome/browser/ui/webui/tracing_ui.cc
index 9e61feec58197500016fddf0f61cde3ae1de33d8..ca09f890e3d1f62ea283e9b9c98729c5e58863ab 100644
--- a/chrome/browser/ui/webui/tracing_ui.cc
+++ b/chrome/browser/ui/webui/tracing_ui.cc
@@ -402,8 +402,8 @@ void TracingMessageHandler::OnBeginTracing(const ListValue* args) {
   bool ok = args->GetBoolean(0, &system_tracing_requested);
   DCHECK(ok);
 
-  std::string chrome_categories;
-  ok = args->GetString(1, &chrome_categories);
+  std::string tag_patterns;
+  ok = args->GetString(1, &tag_patterns);
   DCHECK(ok);
 
   trace_enabled_ = true;
@@ -411,7 +411,7 @@ void TracingMessageHandler::OnBeginTracing(const ListValue* args) {
   //              Ex: Multiple about:gpu traces can not trace simultaneously.
   // TODO(nduca) send feedback to javascript about whether or not BeginTracing
   //             was successful.
-  TraceController::GetInstance()->BeginTracing(this, chrome_categories);
+  TraceController::GetInstance()->BeginTracing(this, tag_patterns);
 
   if (system_tracing_requested) {
 #if defined(OS_CHROMEOS)