Add a Clock and TickClock interface for mocking out time

base/base.gypi

 # Copyright (c) 2012 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.
 
 {
   'target_defaults': {
     'variables': {
       'base_target': 0,
     },
     'target_conditions': [
@@ skipping 70 matching lines @@
           'bits.h',
           'build_time.cc',
           'build_time.h',
           'callback.h',
           'callback_helpers.h',
           'callback_internal.cc',
           'callback_internal.h',
           'cancelable_callback.h',
           'chromeos/chromeos_version.cc',
           'chromeos/chromeos_version.h',
+          'clock.cc',
+          'clock.h',
           'command_line.cc',
           'command_line.h',
           'compiler_specific.h',
           'containers/linked_list.h',
           'containers/mru_cache.h',
           'containers/small_map.h',
           'containers/stack_container.h',
           'cpu.cc',
           'cpu.h',
           'critical_closure.h',
@@ skipping 18 matching lines @@
           'debug/stack_trace_android.cc',
           'debug/stack_trace_ios.mm',
           'debug/stack_trace_posix.cc',
           'debug/stack_trace_win.cc',
           'debug/trace_event.cc',
           'debug/trace_event.h',
           'debug/trace_event_android.cc',
           'debug/trace_event_impl.cc',
           'debug/trace_event_impl.h',
           'debug/trace_event_win.cc',
+          'default_clock.cc',
+          'default_clock.h',
+          'default_tick_clock.cc',
+          'default_tick_clock.h',
           'environment.cc',
           'environment.h',
           'file_descriptor_posix.h',
           'file_path.cc',
           'file_path.h',
           'file_util.cc',
           'file_util.h',
           'file_util_android.cc',
           'file_util_linux.cc',
           'file_util_mac.mm',
@@ skipping 320 matching lines @@
           'threading/thread_local_win.cc',
           'threading/thread_restrictions.h',
           'threading/thread_restrictions.cc',
           'threading/watchdog.cc',
           'threading/watchdog.h',
           'threading/worker_pool.h',
           'threading/worker_pool.cc',
           'threading/worker_pool_posix.cc',
           'threading/worker_pool_posix.h',
           'threading/worker_pool_win.cc',
+          'tick_clock.cc',
+          'tick_clock.h',
           'time.cc',
           'time.h',
           'time_mac.cc',
           'time_posix.cc',
           'time_win.cc',
           'timer.cc',
           'timer.h',
           'tracked_objects.cc',
           'tracked_objects.h',
           'tracking_info.cc',
@@ skipping 243 matching lines @@
           # Remove all unnecessary files for build_nexe.py to avoid exceeding
           # command-line-string limitation when building NaCl on Windows.
           ['OS == "win" and >(nacl_untrusted_build)==1', {
               'sources/': [ ['exclude', '\\.h$'] ],
           }],
         ],
       }],
     ],
   },
 }