Add base::UnguessableToken

base/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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 547 matching lines @@
     "native_library.cc",
     "native_library.h",
     "native_library_ios.mm",
     "native_library_mac.mm",
     "native_library_posix.cc",
     "native_library_win.cc",
     "nix/mime_util_xdg.cc",
     "nix/mime_util_xdg.h",
     "nix/xdg_util.cc",
     "nix/xdg_util.h",
+    "nonce.cc",
+    "nonce.h",
     "numerics/safe_conversions.h",
     "numerics/safe_conversions_impl.h",
     "numerics/safe_math.h",
     "numerics/safe_math_impl.h",
     "observer_list.h",
     "observer_list_threadsafe.h",
     "optional.h",
     "os_compat_android.cc",
     "os_compat_android.h",
     "os_compat_nacl.cc",
@@ skipping 1276 matching lines @@
     "metrics/histogram_unittest.cc",
     "metrics/metrics_hashes_unittest.cc",
     "metrics/persistent_histogram_allocator_unittest.cc",
     "metrics/persistent_memory_allocator_unittest.cc",
     "metrics/persistent_sample_map_unittest.cc",
     "metrics/sample_map_unittest.cc",
     "metrics/sample_vector_unittest.cc",
     "metrics/sparse_histogram_unittest.cc",
     "metrics/statistics_recorder_unittest.cc",
     "native_library_unittest.cc",
+    "nonce_unittest.cc",
     "numerics/safe_numerics_unittest.cc",
     "observer_list_unittest.cc",
     "optional_unittest.cc",
     "os_compat_android_unittest.cc",
     "path_service_unittest.cc",
     "pickle_unittest.cc",
     "posix/file_descriptor_shuffle_unittest.cc",
     "posix/unix_domain_socket_linux_unittest.cc",
     "power_monitor/power_monitor_unittest.cc",
     "process/memory_unittest.cc",
@@ skipping 570 matching lines @@
     testonly = true
     deps = [
       ":base_java",
     ]
     java_files = [
       "test/android/java/src/org/chromium/base/ContentUriTestUtils.java",
       "test/android/java/src/org/chromium/base/TestSystemMessageHandler.java",
     ]
   }
 }