[Extensions] Short-circuit activity logging if not enabled

chrome/browser/extensions/activity_log/activity_log_browsertest.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdint.h>
 
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 59 matching lines @@
   host_resolver()->AddRule("*", "127.0.0.1");
   ASSERT_TRUE(StartEmbeddedTestServer());
   uint16_t port = embedded_test_server()->port();
 
   // Get the extension (chrome/test/data/extensions/activity_log)
   const Extension* ext =
       LoadExtension(test_data_dir_.AppendASCII("activity_log"));
   ASSERT_TRUE(ext);
 
   ActivityLog* activity_log = ActivityLog::GetInstance(profile());
+  activity_log->SetWatchdogAppActiveForTesting(true);
   ASSERT_TRUE(activity_log);
 
   // Disable rate limiting in PrerenderManager
   prerender::PrerenderManager* prerender_manager =
       prerender::PrerenderManagerFactory::GetForProfile(profile());
   ASSERT_TRUE(prerender_manager);
   prerender_manager->mutable_config().rate_limit_enabled = false;
   // Increase prerenderer limits, otherwise this test fails
   // on Windows XP.
   prerender_manager->mutable_config().max_bytes = 1000 * 1024 * 1024;
@@ skipping 31 matching lines @@
       "",
       -1,
       base::Bind(
           ActivityLogPrerenderTest::Prerender_Arguments, ext->id(), port));
 
   // Allow invocation of Prerender_Arguments
   base::MessageLoop::current()->Run();
 }
 
 }  // namespace extensions