Add some tracing for Profiles and Extensions.

chrome/browser/extensions/extension_service.cc

Index: chrome/browser/extensions/extension_service.cc
diff --git a/chrome/browser/extensions/extension_service.cc b/chrome/browser/extensions/extension_service.cc
index e13371fb66a1d2b28e4ac85188d77eefb76a2e68..adc9e4fe7f33a096cd8d73c65f75ab6356339d2a 100644
--- a/chrome/browser/extensions/extension_service.cc
+++ b/chrome/browser/extensions/extension_service.cc
@@ -16,6 +16,7 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time/time.h"
+#include "base/trace_event/trace_event.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/content_settings/content_settings_internal_extension_provider.h"
@@ -384,7 +385,7 @@ const Extension* ExtensionService::GetExtensionById(
 
 void ExtensionService::Init() {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
+  TRACE_EVENT0("browser,startup", "ExtensionService::Init");
   base::Time begin_time = base::Time::Now();
 
   DCHECK(!is_ready());  // Can't redo init.
@@ -2048,6 +2049,7 @@ const Extension* ExtensionService::GetPendingExtensionUpdate(
 
 void ExtensionService::RegisterContentSettings(
     HostContentSettingsMap* host_content_settings_map) {
+  TRACE_EVENT0("browser,startup", "ExtensionService::RegisterContentSettings");
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   host_content_settings_map->RegisterProvider(
       HostContentSettingsMap::INTERNAL_EXTENSION_PROVIDER,