[tracing] Show the local storage databases under dom_storage

content/browser/dom_storage/dom_storage_area.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_area.h"
 
 #include <inttypes.h>
 
 #include <algorithm>
 #include <cctype>  // for std::isalnum
@@ skipping 356 matching lines @@
   if (commit_batch_) {
     auto* commit_batch_mad = pmd->CreateAllocatorDump(name + "/commit_batch");
     commit_batch_mad->AddScalar(
         base::trace_event::MemoryAllocatorDump::kNameSize,
         base::trace_event::MemoryAllocatorDump::kUnitsBytes,
         commit_batch_->GetDataSize());
     if (system_allocator_name)
       pmd->AddSuballocation(commit_batch_mad->guid(), system_allocator_name);
   }
 
+  // Report memory usage for local storage backing. The session storage usage
+  // will be reported by DOMStorageContextImpl.
+  if (namespace_id_ == kLocalStorageNamespaceId && backing_)
+    backing_->ReportMemoryUsage(pmd, name + "/local_storage");
+
   // Do not add storage map usage if less than 1KB.
   if (map_->bytes_used() < 1024)
     return;
 
   auto* map_mad = pmd->CreateAllocatorDump(name + "/storage_map");
   map_mad->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
                      base::trace_event::MemoryAllocatorDump::kUnitsBytes,
                      map_->bytes_used());
   if (system_allocator_name)
     pmd->AddSuballocation(map_mad->guid(), system_allocator_name);
-  // TODO(ssid): Add memory usage of local backing storage crbug.com/605785.
 }
 
 void DOMStorageArea::InitialImportIfNeeded() {
   if (is_initial_import_done_)
     return;
 
   DCHECK(backing_.get());
 
   base::TimeTicks before = base::TimeTicks::Now();
   DOMStorageValuesMap initial_values;
@@ skipping 141 matching lines @@
         commit_batch_->clear_all_first,
         commit_batch_->changed_values);
     DCHECK(success);
   }
   commit_batch_.reset();
   backing_.reset();
   session_storage_backing_ = NULL;
 }
 
 }  // namespace content