Report expected task queueing time via UMA

components/scheduler/BUILD.gn

 # Copyright 2015 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.
 
 # GYP version: components/scheduler.gypi:scheduler
 component("scheduler") {
   sources = [
     "base/cancelable_closure_holder.cc",
     "base/cancelable_closure_holder.h",
     "base/enqueue_order.cc",
@@ skipping 43 matching lines @@
     "child/worker_scheduler.cc",
     "child/worker_scheduler.h",
     "child/worker_scheduler_impl.cc",
     "child/worker_scheduler_impl.h",
     "renderer/auto_advancing_virtual_time_domain.cc",
     "renderer/auto_advancing_virtual_time_domain.h",
     "renderer/deadline_task_runner.cc",
     "renderer/deadline_task_runner.h",
     "renderer/idle_time_estimator.cc",
     "renderer/idle_time_estimator.h",
+    "renderer/queueing_time_estimator.cc",
+    "renderer/queueing_time_estimator.h",
     "renderer/render_widget_scheduling_state.cc",
     "renderer/render_widget_scheduling_state.h",
     "renderer/render_widget_signals.cc",
     "renderer/render_widget_signals.h",
     "renderer/renderer_scheduler.cc",
     "renderer/renderer_scheduler.h",
     "renderer/renderer_scheduler_impl.cc",
     "renderer/renderer_scheduler_impl.h",
     "renderer/renderer_web_scheduler_impl.cc",
     "renderer/renderer_web_scheduler_impl.h",
@@ skipping 57 matching lines @@
     "child/idle_helper_unittest.cc",
     "child/scheduler_helper_unittest.cc",
     "child/scheduler_tqm_delegate_for_test.cc",
     "child/scheduler_tqm_delegate_for_test.h",
     "child/scheduler_tqm_delegate_impl_unittest.cc",
     "child/webthread_impl_for_worker_scheduler_unittest.cc",
     "child/worker_scheduler_impl_unittest.cc",
     "renderer/auto_advancing_virtual_time_domain_unittest.cc",
     "renderer/deadline_task_runner_unittest.cc",
     "renderer/idle_time_estimator_unittest.cc",
+    "renderer/queueing_time_estimator_unittest.cc",
     "renderer/render_widget_signals_unittest.cpp",
     "renderer/renderer_scheduler_impl_unittest.cc",
     "renderer/task_cost_estimator_unittest.cc",
     "renderer/throttling_helper_unittest.cc",
     "renderer/user_model_unittest.cc",
     "renderer/web_view_scheduler_impl_unittest.cc",
     "renderer/webthread_impl_for_renderer_scheduler_unittest.cc",
   ]
 
   deps = [
@@ skipping 18 matching lines @@
 
   deps = [
     "//third_party/WebKit/public:blink",
   ]
 
   public_deps = [
     ":scheduler",
     "//base",
   ]
 }