NQE: Add net log event if the metric changes substantially

net/BUILD.gn

 # Copyright (c) 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.
 
 import("//build/buildflag_header.gni")
 import("//build/config/chromecast_build.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
@@ skipping 4325 matching lines @@
     "http2/tools/random_decoder_test.h",
     "http2/tools/random_util.cc",
     "http2/tools/random_util.h",
     "log/file_net_log_observer_unittest.cc",
     "log/net_log_capture_mode_unittest.cc",
     "log/net_log_unittest.cc",
     "log/net_log_util_unittest.cc",
     "log/trace_net_log_observer_unittest.cc",
     "log/write_to_file_net_log_observer_unittest.cc",
     "nqe/effective_connection_type_unittest.cc",
+    "nqe/event_creator_unittest.cc",
     "nqe/network_qualities_prefs_manager_unittest.cc",
     "nqe/network_quality_estimator_unittest.cc",
     "nqe/network_quality_store_unittest.cc",
     "nqe/observation_buffer_unittest.cc",
     "nqe/socket_watcher_unittest.cc",
     "nqe/throughput_analyzer_unittest.cc",
     "proxy/dhcp_proxy_script_adapter_fetcher_win_unittest.cc",
     "proxy/dhcp_proxy_script_fetcher_factory_unittest.cc",
     "proxy/dhcp_proxy_script_fetcher_win_unittest.cc",
     "proxy/mojo_proxy_resolver_factory_impl_unittest.cc",
@@ skipping 1349 matching lines @@
       "tools/transport_security_state_generator/trie/trie_writer.cc",
       "tools/transport_security_state_generator/trie/trie_writer.h",
     ]
     deps = [
       "//base",
       "//crypto",
       "//third_party/boringssl",
     ]
   }
 }