Adding instrumentation to locate the source of jankiness.

storage/browser/blob/view_blob_internals_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 "storage/browser/blob/view_blob_internals_job.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/format_macros.h"
 #include "base/i18n/number_formatting.h"
 #include "base/i18n/time_formatting.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
+#include "base/profiler/scoped_profile.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "net/base/escape.h"
 #include "net/base/net_errors.h"
 #include "net/url_request/url_request.h"
 #include "storage/browser/blob/blob_storage_context.h"
 #include "storage/common/blob/blob_data.h"
 
@@ skipping 100 matching lines @@
 void ViewBlobInternalsJob::Kill() {
   net::URLRequestSimpleJob::Kill();
   weak_factory_.InvalidateWeakPtrs();
 }
 
 int ViewBlobInternalsJob::GetData(
     std::string* mime_type,
     std::string* charset,
     std::string* data,
     const net::CompletionCallback& callback) const {
+  // TODO(vadimt): Remove ScopedProfile below once crbug.com/422489 is fixed.
+  tracked_objects::ScopedProfile tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION("422489 ViewBlobInternalsJob::GetData"));
+
   mime_type->assign("text/html");
   charset->assign("UTF-8");
 
   data->clear();
   StartHTML(data);
   if (blob_storage_context_->blob_map_.empty())
     data->append(kEmptyBlobStorageMessage);
   else
     GenerateHTML(data);
   EndHTML(data);
@@ skipping 89 matching lines @@
     }
 
     if (has_multi_items)
       EndHTMLList(out);
   }
 
   EndHTMLList(out);
 }
 
 }  // namespace storage