[not for commit] Add necessary code to enable per-request CPU benchmarking

third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
     rights reserved.
     Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
@@ skipping 450 matching lines @@
   SCOPED_BLINK_UMA_HISTOGRAM_TIMER("Blink.Fetch.RequestResourceTime");
   DCHECK(request.options().synchronousPolicy == RequestAsynchronously ||
          factory.type() == Resource::Raw ||
          factory.type() == Resource::XSLStyleSheet);
 
   context().populateResourceRequest(
       factory.type(), request.clientHintsPreferences(),
       request.getResourceWidth(), resourceRequest);
 
   // TODO(dproy): Remove this. http://crbug.com/659666
-  TRACE_EVENT1("blink", "ResourceFetcher::requestResource", "url",
+  TRACE_EVENT1("blink,loading", "ResourceFetcher::requestResource", "url",
                urlForTraceEvent(request.url()));
 
   if (!request.url().isValid())
     return nullptr;
 
   resourceRequest.setPriority(computeLoadPriority(
       factory.type(), request, ResourcePriority::NotVisible));
   initializeResourceRequest(resourceRequest, factory.type(), request.defer());
   network_instrumentation::resourcePrioritySet(identifier,
                                                resourceRequest.priority());
@@ skipping 1020 matching lines @@
   visitor->trace(m_context);
   visitor->trace(m_archive);
   visitor->trace(m_loaders);
   visitor->trace(m_nonBlockingLoaders);
   visitor->trace(m_documentResources);
   visitor->trace(m_preloads);
   visitor->trace(m_resourceTimingInfoMap);
 }
 
 }  // namespace blink