Add trace to the caller of QuotaManager::GetAvailableSpace

chrome/browser/ui/webui/quota_internals/quota_internals_proxy.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/browser/ui/webui/quota_internals/quota_internals_proxy.h"
 
 #include <set>
 #include <string>
 
 #include "base/bind.h"
+#include "base/trace_event/trace_event.h"
 #include "chrome/browser/ui/webui/quota_internals/quota_internals_handler.h"
 #include "chrome/browser/ui/webui/quota_internals/quota_internals_types.h"
 #include "net/base/net_util.h"
 
 using content::BrowserThread;
 
 namespace quota_internals {
 
 QuotaInternalsProxy::QuotaInternalsProxy(QuotaInternalsHandler* handler)
     : handler_(handler),
       weak_factory_(this) {
 }
 
 void QuotaInternalsProxy::RequestInfo(
     scoped_refptr<storage::QuotaManager> quota_manager) {
+  // crbug.com/349708
+  TRACE_EVENT0("io", "QuotaInternalsProxy::RequestInfo");
+
   DCHECK(quota_manager.get());
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         base::Bind(&QuotaInternalsProxy::RequestInfo, this, quota_manager));
     return;
   }
 
   quota_manager_ = quota_manager;
   quota_manager_->GetAvailableSpace(
@@ skipping 185 matching lines @@
   DCHECK(quota_manager_.get());
   quota_manager_->GetHostUsage(host,
                                type,
                                base::Bind(&QuotaInternalsProxy::DidGetHostUsage,
                                           weak_factory_.GetWeakPtr(),
                                           host,
                                           type));
 }
 
 }  // namespace quota_internals