Rework UMAHistogramHelper and StatisticsDeltaReader into [Chrome]HistogramTester.

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.
 
 import("//build/config/android/rules.gni")
 import("//build/config/ui.gni")
 
 component("base") {
   sources = [
     "third_party/dmg_fp/dmg_fp.h",
@@ skipping 1176 matching lines @@
     "synchronization/lock_unittest.cc",
     "synchronization/waitable_event_unittest.cc",
     "synchronization/waitable_event_watcher_unittest.cc",
     "sys_info_unittest.cc",
     "system_monitor/system_monitor_unittest.cc",
     "task/cancelable_task_tracker_unittest.cc",
     "task_runner_util_unittest.cc",
     "template_util_unittest.cc",
     "test/expectations/expectation_unittest.cc",
     "test/expectations/parser_unittest.cc",
-    "test/statistics_delta_reader_unittest.cc",
+    "test/histogram_tester_unittest.cc",
     "test/test_reg_util_win_unittest.cc",
     "test/trace_event_analyzer_unittest.cc",
     "threading/non_thread_safe_unittest.cc",
     "threading/platform_thread_unittest.cc",
     "threading/sequenced_worker_pool_unittest.cc",
     "threading/simple_thread_unittest.cc",
     "threading/thread_checker_unittest.cc",
     "threading/thread_collision_warner_unittest.cc",
     "threading/thread_id_name_manager_unittest.cc",
     "threading/thread_local_storage_unittest.cc",
@@ skipping 204 matching lines @@
       "android/java/templates/NativeLibraries.template",
     ]
     inputs = [
       "android/java/templates/native_libraries_array.h",
     ]
 
     package_name = "org/chromium/base/library_loader"
     include_path = "android/java/templates"
   }
 }