Adding instrumentation to locate the source of jankiness.

content/browser/appcache/appcache_url_request_job.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 "content/browser/appcache/appcache_url_request_job.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 364 matching lines @@
     info_ = NULL;
     cache_ = NULL;
     group_ = NULL;
     range_response_info_.reset();
     net::URLRequestJob::Kill();
     weak_factory_.InvalidateWeakPtrs();
   }
 }
 
 net::LoadState AppCacheURLRequestJob::GetLoadState() const {
+  // TODO(pkasting): Remove ScopedTracker below once crbug.com/455952 is
+  // fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "455952 AppCacheURLRequestJob::GetLoadState"));
   if (!has_been_started())
     return net::LOAD_STATE_IDLE;
   if (!has_delivery_orders())
     return net::LOAD_STATE_WAITING_FOR_APPCACHE;
   if (delivery_type_ != APPCACHED_DELIVERY)
     return net::LOAD_STATE_IDLE;
   if (!info_.get())
     return net::LOAD_STATE_WAITING_FOR_APPCACHE;
   if (reader_.get() && reader_->IsReadPending())
     return net::LOAD_STATE_READING_RESPONSE;
@@ skipping 51 matching lines @@
     return;
   }
 
   // If multiple ranges are requested, we play dumb and
   // return the entire response with 200 OK.
   if (ranges.size() == 1U)
     range_requested_ = ranges[0];
 }
 
 }  // namespace content