[Extensions] Fix incorrect counting prefs in activity log

chrome/browser/extensions/activity_log/activity_log_unittest.cc

Index: chrome/browser/extensions/activity_log/activity_log_unittest.cc
diff --git a/chrome/browser/extensions/activity_log/activity_log_unittest.cc b/chrome/browser/extensions/activity_log/activity_log_unittest.cc
index e11d227d69b4349599ce4eebf9ac9b06bf6bd3f9..cd8d9b32312ee39b03e81b3b0423ebc9d191f2b2 100644
--- a/chrome/browser/extensions/activity_log/activity_log_unittest.cc
+++ b/chrome/browser/extensions/activity_log/activity_log_unittest.cc
@@ -430,6 +430,8 @@ class ActivityLogTestWithoutSwitch : public ActivityLogTest {
 };
 
 TEST_F(ActivityLogTestWithoutSwitch, TestShouldLog) {
+  static_cast<TestExtensionSystem*>(
+      ExtensionSystem::Get(profile()))->SetReady();
   ActivityLog* activity_log = ActivityLog::GetInstance(profile());
   scoped_refptr<const Extension> empty_extension =
       test_util::CreateEmptyExtension();