[tracing] Add a memory dump provider for DOM storage

content/browser/dom_storage/dom_storage_namespace.cc

 // Copyright 2013 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/dom_storage/dom_storage_namespace.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "content/browser/dom_storage/dom_storage_area.h"
@@ skipping 158 matching lines @@
 
 unsigned int DOMStorageNamespace::CountInMemoryAreas() const {
   unsigned int area_count = 0;
   for (AreaMap::const_iterator it = areas_.begin(); it != areas_.end(); ++it) {
     if (it->second.area_->IsLoadedInMemory())
       ++area_count;
   }
   return area_count;
 }
 
+void DOMStorageNamespace::OnMemoryDump(
+    base::trace_event::ProcessMemoryDump* pmd) {
+  DCHECK(task_runner_->IsRunningOnPrimarySequence());
+  for (const auto& it : areas_)
+    it.second.area_->OnMemoryDump(pmd);
+}
+
 DOMStorageNamespace::AreaHolder*
 DOMStorageNamespace::GetAreaHolder(const GURL& origin) {
   AreaMap::iterator found = areas_.find(origin);
   if (found == areas_.end())
     return NULL;
   return &(found->second);
 }
 
 // AreaHolder
 
 DOMStorageNamespace::AreaHolder::AreaHolder()
     : open_count_(0) {
 }
 
 DOMStorageNamespace::AreaHolder::AreaHolder(
     DOMStorageArea* area, int count)
     : area_(area), open_count_(count) {
 }
 
 DOMStorageNamespace::AreaHolder::AreaHolder(const AreaHolder& other) = default;
 
 DOMStorageNamespace::AreaHolder::~AreaHolder() {
 }
 
 }  // namespace content