[tracing] Show the local storage databases under dom_storage

content/browser/dom_storage/dom_storage_database.cc

Index: content/browser/dom_storage/dom_storage_database.cc
diff --git a/content/browser/dom_storage/dom_storage_database.cc b/content/browser/dom_storage/dom_storage_database.cc
index d11aad76540c65aa77527f1bf741c172943aa7ad..2f47c3af03e5262bf6a2588fc1b05b7b1ec604d1 100644
--- a/content/browser/dom_storage/dom_storage_database.cc
+++ b/content/browser/dom_storage/dom_storage_database.cc
@@ -135,6 +135,13 @@ bool DOMStorageDatabase::CommitChanges(bool clear_all_first,
   return success;
 }
 
+void DOMStorageDatabase::ReportMemoryUsage(
+    base::trace_event::ProcessMemoryDump* pmd,
+    const std::string& name) {
+  if (IsOpen())
+    db_->ReportMemoryUsage(pmd, name);
+}
+
 bool DOMStorageDatabase::LazyOpen(bool create_if_needed) {
   if (failed_to_open_) {
     // Don't try to open a database that we know has failed