Add TimeToScrollUpdateSwapBegin2 in RAPPOR

content/browser/renderer_host/input/render_widget_host_latency_tracker.cc

Index: content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
diff --git a/content/browser/renderer_host/input/render_widget_host_latency_tracker.cc b/content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
index a8d3ac23f52d9612d76f3b27e9185f8c9c04e02b..9334428d5f997700f2d87875874e0993a5bda544 100644
--- a/content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
+++ b/content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
@@ -9,6 +9,7 @@
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 #include "build/build_config.h"
+#include "components/rappor/rappor_service.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "ui/events/blink/web_input_event_traits.h"
 
@@ -237,7 +238,24 @@ void ComputeScrollLatencyHistograms(
                                      gpu_swap_end_component);
 }
 
+uint64_t RapporHistogramBucketIndex(int64_t ms) {
+  if (ms < 10)
+    return 0;
+  if (ms < 20)
+    return 1;
+  if (ms < 30)
+    return 2;
+  if (ms < 40)
+    return 3;
+  if (ms < 50)
+    return 4;
+  if (ms < 60)
+    return 5;

[ncarter (slow), 2016/12/01 23:33:46]

What about 6?

[Navid Zolghadr, 2016/12/08 17:37:29]

This is now removed as I reported it without any bucket.

+  return 7;
+}
+
 void ComputeTouchAndWheelScrollLatencyHistograms(
+    RenderWidgetHostImpl* render_widget_host_impl,
     const ui::LatencyInfo::LatencyComponent& gpu_swap_begin_component,
     const ui::LatencyInfo::LatencyComponent& gpu_swap_end_component,
     int64_t latency_component_id,
@@ -269,6 +287,27 @@ void ComputeTouchAndWheelScrollLatencyHistograms(
           "Event.Latency.ScrollUpdate." + event_type_name +
               ".TimeToScrollUpdateSwapBegin2",
           original_component, gpu_swap_begin_component);
+
+      if (!render_widget_host_impl->delegate())
+        return;
+      rappor::RapporService* rappor_service =
+          render_widget_host_impl->delegate()->getRapporService();
+      if (!rappor_service)
+        return;
+      std::unique_ptr<rappor::Sample> sample =
+          rappor_service->CreateSample(rappor::UMA_RAPPOR_TYPE);
+      sample->SetStringField(
+          "Domain",
+          render_widget_host_impl->delegate()->getRapporCommittedUrl());

[Navid Zolghadr, 2016/11/10 21:49:19]

I was going to create some helper methods in my next CL along with the next
Rappor metric maybe somewhere in rappor_utils similar to the UMA ones we have.

Steven, is that okay or are there maybe existing ones? I couldn't find any as
far as I searched.

[Steven Holte, 2016/11/10 22:49:45]

It seems like this value is non-PII, so it should be fine to send this as a
non-noised int field e.g SetUInt64Field("Latency", delta.InMicroseconds,
rappor::NO_NOISE);

[Navid Zolghadr, 2016/12/08 17:37:29]

Done. I didn't find anywhere else that this is used. I used uint64-field in
rappor.xml. Is that correct?

+      uint64_t bucket_index =
+          RapporHistogramBucketIndex((gpu_swap_begin_component.last_event_time -
+                                      original_component.first_event_time)
+                                         .InMicroseconds());
+      sample->SetFlagsField("Bucket", uint64_t(1) << bucket_index, 7);
+      rappor_service->RecordSampleObj(
+          "Event.Latency.ScrollUpdate.Touch.TimeToScrollUpdateSwapBegin2."
+          "Rappor",
+          std::move(sample));
     }
   } else {
     // No original component found.
@@ -356,13 +395,15 @@ void AddLatencyInfoComponentIds(LatencyInfo* latency,
 
 }  // namespace
 
-RenderWidgetHostLatencyTracker::RenderWidgetHostLatencyTracker()
+RenderWidgetHostLatencyTracker::RenderWidgetHostLatencyTracker(
+    RenderWidgetHostImpl* render_widget_host_impl)
     : last_event_id_(0),
       latency_component_id_(0),
       device_scale_factor_(1),
       has_seen_first_gesture_scroll_update_(false),
       multi_finger_gesture_(false),
-      touch_start_default_prevented_(false) {}
+      touch_start_default_prevented_(false),
+      render_widget_host_impl(render_widget_host_impl) {}
 
 RenderWidgetHostLatencyTracker::~RenderWidgetHostLatencyTracker() {}
 
@@ -701,8 +742,8 @@ void RenderWidgetHostLatencyTracker::OnFrameSwapped(
   if (source_event_type == ui::SourceEventType::WHEEL ||
       source_event_type == ui::SourceEventType::TOUCH) {
     ComputeTouchAndWheelScrollLatencyHistograms(
-        gpu_swap_begin_component, gpu_swap_end_component, latency_component_id_,
-        latency,
+        render_widget_host_impl, gpu_swap_begin_component,
+        gpu_swap_end_component, latency_component_id_, latency,
         source_event_type == ui::SourceEventType::WHEEL ? "Wheel" : "Touch");
   }