Use leveldb_env::OpenDB() to open leveldb databases.

third_party/leveldatabase/env_chromium.cc

Index: third_party/leveldatabase/env_chromium.cc
diff --git a/third_party/leveldatabase/env_chromium.cc b/third_party/leveldatabase/env_chromium.cc
index 928d4be2027d0ab979c2e1f8aa9b1029b2e133b8..37e2db36fa2fdbffd7610ae14543c5912b2119ad 100644
--- a/third_party/leveldatabase/env_chromium.cc
+++ b/third_party/leveldatabase/env_chromium.cc
@@ -1193,8 +1193,7 @@ class DBTracker::MemoryDumpProvider
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
                     base::trace_event::ProcessMemoryDump* pmd) override {
     auto db_visitor = [&](TrackedDB* db) {
-      std::string db_dump_name = base::StringPrintf(
-          "leveldatabase/0x%" PRIXPTR, reinterpret_cast<uintptr_t>(db));
+      std::string db_dump_name = DBTracker::GetMemoryDumpName(db);
       auto* db_dump = pmd->CreateAllocatorDump(db_dump_name.c_str());
 
       uint64_t db_memory_usage = 0;
@@ -1241,6 +1240,11 @@ DBTracker* DBTracker::GetInstance() {
   return instance;
 }
 
+std::string DBTracker::GetMemoryDumpName(leveldb::DB* db) {
+  return base::StringPrintf("leveldatabase/0x%" PRIXPTR,
+                            reinterpret_cast<uintptr_t>(db));
+}
+
 leveldb::Status DBTracker::OpenDatabase(const leveldb::Options& options,
                                         const std::string& name,
                                         TrackedDB** dbptr) {