Add tracing to prefs for analyzing startup performance

BUG=222350

Review URL: https://chromiumcodereview.appspot.com/16236003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@203998 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/prefs/browser_prefs.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/prefs/browser_prefs.h"
 
 #include "apps/prefs.h"
+#include "base/debug/trace_event.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/about_flags.h"
@@ -278,6 +279,7 @@ void RegisterLocalState(PrefRegistrySimple* registry) {
 }
 
 void RegisterUserPrefs(user_prefs::PrefRegistrySyncable* registry) {
+  TRACE_EVENT0("browser", "chrome::RegisterUserPrefs");
   // User prefs. Please keep this list alphabetized.
   AlternateErrorPageTabObserver::RegisterUserPrefs(registry);
   autofill::AutofillDialogControllerImpl::RegisterUserPrefs(registry);

chrome/browser/prefs/chrome_pref_service_factory.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/prefs/chrome_pref_service_factory.h"
 
 #include "base/bind.h"
+#include "base/debug/trace_event.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/metrics/histogram.h"
@@ -118,6 +119,7 @@ PrefServiceSyncable* CreateProfilePrefs(
     const scoped_refptr<PrefStore>& extension_prefs,
     const scoped_refptr<user_prefs::PrefRegistrySyncable>& pref_registry,
     bool async) {
+  TRACE_EVENT0("browser", "chrome_prefs::CreateProfilePrefs");
   PrefServiceSyncableBuilder builder;
   PrepareBuilder(&builder,
                  pref_filename,

chrome/browser/prefs/pref_service_syncable_builder.cc

@@ -4,6 +4,7 @@
 
 #include "chrome/browser/prefs/pref_service_syncable_builder.h"
 
+#include "base/debug/trace_event.h"
 #include "base/prefs/default_pref_store.h"
 #include "base/prefs/pref_notifier_impl.h"
 #include "base/prefs/pref_value_store.h"
@@ -43,6 +44,7 @@ PrefServiceSyncableBuilder::WithCommandLine(CommandLine* command_line) {
 
 PrefServiceSyncable* PrefServiceSyncableBuilder::CreateSyncable(
     user_prefs::PrefRegistrySyncable* pref_registry) {
+  TRACE_EVENT0("browser", "PrefServiceSyncableBuilder::CreateSyncable");
   PrefNotifierImpl* pref_notifier = new PrefNotifierImpl();
   PrefServiceSyncable* pref_service = new PrefServiceSyncable(
       pref_notifier,