Add missing dumpfile.cc to leveldatabase target in GN build.

build/secondary/third_party/leveldatabase/BUILD.gn

 # Copyright 2014 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.
 
 # Snappy is a compression library we use.
 # TODO(brettw) It's not clear why this needs to be parameterized.
 
 import("//testing/test.gni")
 
 use_snappy = true
@@ skipping 16 matching lines @@
     "port/port_chromium.cc",
     "port/port_chromium.h",
     "src/db/builder.cc",
     "src/db/builder.h",
     "src/db/db_impl.cc",
     "src/db/db_impl.h",
     "src/db/db_iter.cc",
     "src/db/db_iter.h",
     "src/db/dbformat.cc",
     "src/db/dbformat.h",
+    "src/db/dumpfile.cc",
     "src/db/filename.cc",
     "src/db/filename.h",
     "src/db/log_format.h",
     "src/db/log_reader.cc",
     "src/db/log_reader.h",
     "src/db/log_writer.cc",
     "src/db/log_writer.h",
     "src/db/memtable.cc",
     "src/db/memtable.h",
     "src/db/repair.cc",
     "src/db/skiplist.h",
     "src/db/snapshot.h",
     "src/db/table_cache.cc",
     "src/db/table_cache.h",
     "src/db/version_edit.cc",
     "src/db/version_edit.h",
     "src/db/version_set.cc",
     "src/db/version_set.h",
     "src/db/write_batch.cc",
     "src/db/write_batch_internal.h",
     "src/helpers/memenv/memenv.cc",
     "src/helpers/memenv/memenv.h",
     "src/include/leveldb/cache.h",
     "src/include/leveldb/comparator.h",
     "src/include/leveldb/db.h",
+    "src/include/leveldb/dumpfile.h",
     "src/include/leveldb/env.h",
     "src/include/leveldb/filter_policy.h",
     "src/include/leveldb/iterator.h",
     "src/include/leveldb/options.h",
     "src/include/leveldb/slice.h",
     "src/include/leveldb/status.h",
     "src/include/leveldb/table.h",
     "src/include/leveldb/table_builder.h",
     "src/include/leveldb/write_batch.h",
     "src/port/port.h",
@@ skipping 257 matching lines @@
     sources = [
       "src/db/write_batch_test.cc",
     ]
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [ "//build/config/compiler:no_chromium_code" ]
     deps = [
       ":leveldb_testutil",
     ]
   }
 }