Added UkmPageLoadMetricsObserver which sends top-level metrics to UKM

chrome/test/base/testing_browser_process.cc

 // Copyright (c) 2012 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 "chrome/test/base/testing_browser_process.h"
 
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/time/default_clock.h"
 #include "base/time/default_tick_clock.h"
@@ skipping 59 matching lines @@
 }
 
 TestingBrowserProcess::TestingBrowserProcess()
     : notification_service_(content::NotificationService::Create()),
       app_locale_("en"),
       is_shutting_down_(false),
       local_state_(nullptr),
       io_thread_(nullptr),
       system_request_context_(nullptr),
       rappor_service_(nullptr),
+      ukm_service_(nullptr),
       platform_part_(new TestingBrowserProcessPlatformPart()) {
 #if BUILDFLAG(ENABLE_EXTENSIONS)
   extensions_browser_client_.reset(
       new extensions::ChromeExtensionsBrowserClient);
   extensions::AppWindowClient::Set(ChromeAppWindowClient::GetInstance());
   extensions::ExtensionsBrowserClient::Set(extensions_browser_client_.get());
 #endif
 }
 
 TestingBrowserProcess::~TestingBrowserProcess() {
@@ skipping 389 matching lines @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
 TestingBrowserProcessInitializer::TestingBrowserProcessInitializer() {
   TestingBrowserProcess::CreateInstance();
 }
 
 TestingBrowserProcessInitializer::~TestingBrowserProcessInitializer() {
   TestingBrowserProcess::DeleteInstance();
 }