EQT: Record the max queueing time from navigation start to navigation away

third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h

Index: third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
diff --git a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
index 06d370b91b3b4bd20329df0e27299ddaada5815a..c1e5c4c5554ab4f995b59ebe6f1746cc237f93bc 100644
--- a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
+++ b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
@@ -12,6 +12,8 @@
 #include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "base/trace_event/trace_log.h"
+#include "components/metrics/single_sample_metrics.h"
+#include "components/metrics/single_sample_metrics_factory_impl.h"
 #include "device/base/synchronization/shared_memory_seqlock_buffer.h"
 #include "platform/scheduler/base/pollable_thread_safe_flag.h"
 #include "platform/scheduler/base/queueing_time_estimator.h"
@@ -492,6 +494,7 @@ class PLATFORM_EXPORT RendererSchedulerImpl
     bool in_idle_period_for_testing;
     bool use_virtual_time;
     bool is_audio_playing;
+    std::unique_ptr<base::SingleSampleMetric> max_queuing_time_histogram;
     std::set<WebViewSchedulerImpl*> web_view_schedulers;  // Not owned.
     RAILModeObserver* rail_mode_observer;                 // Not owned.
     WakeUpBudgetPool* wake_up_budget_pool;                // Not owned.