DevTools: support configurable category filter for trace events callback

content/renderer/devtools/devtools_agent.cc

Index: content/renderer/devtools/devtools_agent.cc
diff --git a/content/renderer/devtools/devtools_agent.cc b/content/renderer/devtools/devtools_agent.cc
index a2415441e25a2263e1476a104a1311d5200a1924..a7efd32645a18ac3e7e439a5e5ae41584a1eee25 100644
--- a/content/renderer/devtools/devtools_agent.cc
+++ b/content/renderer/devtools/devtools_agent.cc
@@ -140,19 +140,31 @@ void DevToolsAgent::clearBrowserCookies() {
   Send(new DevToolsHostMsg_ClearBrowserCookies(routing_id()));
 }
 
-void DevToolsAgent::setTraceEventCallback(TraceEventCallback cb) {
+void DevToolsAgent::unsetTraceEventCallback()
+{
+  TraceLog::GetInstance()->SetEventCallbackDisabled();
+  base::subtle::NoBarrier_Store(&event_callback_, 0);
+}
+
+void DevToolsAgent::setTraceEventCallback(const WebString& category_filter,
+                                          TraceEventCallback cb) {
   TraceLog* trace_log = TraceLog::GetInstance();
   base::subtle::NoBarrier_Store(&event_callback_,
                                 reinterpret_cast<base::subtle::AtomicWord>(cb));
   if (!!cb) {
     trace_log->SetEventCallbackEnabled(base::debug::CategoryFilter(
-        base::debug::CategoryFilter::kDefaultCategoryFilterString),
-        TraceEventCallbackWrapper);
+        category_filter.utf8()), TraceEventCallbackWrapper);
   } else {
     trace_log->SetEventCallbackDisabled();
   }
 }
 
+void DevToolsAgent::setTraceEventCallback(TraceEventCallback cb) {
+  WebString category_filter = WebString::fromUTF8(
+      base::debug::CategoryFilter::kDefaultCategoryFilterString);
+  setTraceEventCallback(category_filter, cb);
+}
+
 // static
 void DevToolsAgent::TraceEventCallbackWrapper(
     base::TimeTicks timestamp,