Adding instrumentation to locate the source of jankiness.

components/invalidation/gcm_network_channel.cc

 // Copyright 2014 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 "base/base64.h"
 #include "base/i18n/time_formatting.h"
 #include "base/metrics/histogram.h"
+#include "base/profiler/scoped_profile.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #if !defined(OS_ANDROID)
 // channel_common.proto defines ANDROID constant that conflicts with Android
 // build. At the same time TiclInvalidationService is not used on Android so it
 // is safe to exclude these protos from Android build.
 #include "google/cacheinvalidation/android_channel.pb.h"
 #include "google/cacheinvalidation/channel_common.pb.h"
 #include "google/cacheinvalidation/types.pb.h"
@@ skipping 198 matching lines @@
     const std::string echo_header("echo-token: " + echo_token_);
     fetcher_->AddExtraRequestHeader(echo_header);
   }
   fetcher_->SetUploadData("application/x-protobuffer", cached_message_);
   fetcher_->Start();
   // Clear message to prevent accidentally resending it in the future.
   cached_message_.clear();
 }
 
 void GCMNetworkChannel::OnURLFetchComplete(const net::URLFetcher* source) {
+  // TODO(vadimt): Remove ScopedProfile below once crbug.com/422577 is fixed.
+  tracked_objects::ScopedProfile tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "422577 GCMNetworkChannel::OnURLFetchComplete"));
+
   DCHECK(CalledOnValidThread());
   DCHECK_EQ(fetcher_, source);
   // Free fetcher at the end of function.
   scoped_ptr<net::URLFetcher> fetcher = fetcher_.Pass();
 
   net::URLRequestStatus status = fetcher->GetStatus();
   diagnostic_info_.last_post_response_code_ =
       status.is_success() ? source->GetResponseCode() : status.error();
 
   if (status.is_success() &&
@@ skipping 213 matching lines @@
     ENUM_CASE(gcm::GCMClient::NOT_SIGNED_IN);
     ENUM_CASE(gcm::GCMClient::INVALID_PARAMETER);
     ENUM_CASE(gcm::GCMClient::ASYNC_OPERATION_PENDING);
     ENUM_CASE(gcm::GCMClient::GCM_DISABLED);
   }
   NOTREACHED();
   return "";
 }
 
 }  // namespace syncer