Fix RenderWidgetHostLatencyTracker handling of multi-finger touch.

content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc

Index: content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc
diff --git a/content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc b/content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc
index a161e2f0938b8dffdf03742c0d3906c14458f076..7dd741d6fa3b2d6e622727bd8e5a7eae256566dc 100644
--- a/content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc
+++ b/content/browser/renderer_host/input/render_widget_host_latency_tracker_unittest.cc
@@ -966,4 +966,122 @@ TEST_F(RenderWidgetHostLatencyTrackerTest, TouchBlockingAndQueueingTime) {
                   touchend_timestamps_ms[2] - touchend_timestamps_ms[1], 1)));
 }
 
+// Some touch input histograms aren't reported for multi-finger touch.

[mfomitchev, 2017/04/06 15:27:04]

aren't -> should not be? Or maybe just say that
Event.Latency.QueueingTime.TouchStartDefaultAllowed should be the only one that
gets reported?

[tdresser, 2017/04/06 20:50:09]

Done.

+TEST_F(RenderWidgetHostLatencyTrackerTest, MultiFingerTouchIgnored) {
+  SyntheticWebTouchEvent event;
+  InputEventAckState ack_state = INPUT_EVENT_ACK_STATE_NOT_CONSUMED;
+
+  {
+    // First touch start.
+    ui::LatencyInfo latency;
+    event.PressPoint(1, 1);
+    tracker()->OnInputEvent(event, &latency);
+    tracker()->OnInputEventAck(event, &latency, ack_state);
+  }
+
+  {
+    // Additional touch start will be ignored.

[mfomitchev, 2017/04/06 15:27:04]

It't not completely ignored, right? We are still logging
Event.Latency.QueueingTime.TouchStartDefaultAllowed, just not the other
metrics..

[tdresser, 2017/04/06 20:50:09]

Done.

+    int touchstart_timestamps_ms[] = {11, 25, 35};
+    ui::LatencyInfo latency;
+    event.PressPoint(1, 1);
+    tracker()->OnInputEvent(event, &latency);
+
+    ui::LatencyInfo fake_latency;
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT,
+        tracker()->latency_component_id(), 0,
+        base::TimeTicks() +
+            base::TimeDelta::FromMilliseconds(touchstart_timestamps_ms[0]),
+        1);
+
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_RENDERER_MAIN_COMPONENT, 0, 0,
+        base::TimeTicks() +
+            base::TimeDelta::FromMilliseconds(touchstart_timestamps_ms[1]),
+        1);
+
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_ACK_RWH_COMPONENT, 0, 0,
+        base::TimeTicks() +
+            base::TimeDelta::FromMilliseconds(touchstart_timestamps_ms[2]),
+        1);
+
+    // Call ComputeInputLatencyHistograms directly to avoid OnInputEventAck
+    // overwriting components.
+    tracker()->ComputeInputLatencyHistograms(event.type(),
+                                             tracker()->latency_component_id(),
+                                             fake_latency, ack_state);
+
+    tracker()->OnInputEventAck(event, &latency, ack_state);
+  }
+
+  // Touch start.

[mfomitchev, 2017/04/06 15:27:04]

I am not sure if this comment is helpful (maybe I am missing something).

[tdresser, 2017/04/06 20:50:09]

Copy/paste fail, thanks.

+  EXPECT_THAT(histogram_tester().GetAllSamples(
+                  "Event.Latency.QueueingTime.TouchStartDefaultAllowed"),
+              ElementsAre());
+}
+
+// Some touch input histograms aren't reported for multi-finger touch. Other
+// input modalities shouldn't be impacted by there being an active multi-finger
+// touch gesture.
+TEST_F(RenderWidgetHostLatencyTrackerTest, WheelDuringMultiFingerTouch) {
+  SyntheticWebTouchEvent touch_event;
+  InputEventAckState ack_state = INPUT_EVENT_ACK_STATE_NOT_CONSUMED;
+
+  {
+    // First touch start.
+    ui::LatencyInfo latency;
+    touch_event.PressPoint(1, 1);
+    tracker()->OnInputEvent(touch_event, &latency);
+    tracker()->OnInputEventAck(touch_event, &latency, ack_state);
+  }
+
+  {
+    // Second touch start.
+    ui::LatencyInfo latency;
+    touch_event.PressPoint(1, 1);
+    tracker()->OnInputEvent(touch_event, &latency);
+    tracker()->OnInputEventAck(touch_event, &latency, ack_state);
+  }
+
+  {
+    // Wheel event.
+    ui::LatencyInfo latency;
+    // These numbers are sensitive to where the histogram buckets are.
+    int timestamps_ms[] = {11, 25, 35};
+    auto wheel_event = SyntheticWebMouseWheelEventBuilder::Build(
+        blink::WebMouseWheelEvent::PhaseChanged);
+    tracker()->OnInputEvent(touch_event, &latency);
+
+    ui::LatencyInfo fake_latency;
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT,
+        tracker()->latency_component_id(), 0,
+        base::TimeTicks() + base::TimeDelta::FromMilliseconds(timestamps_ms[0]),
+        1);
+
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_RENDERER_MAIN_COMPONENT, 0, 0,
+        base::TimeTicks() + base::TimeDelta::FromMilliseconds(timestamps_ms[1]),
+        1);
+
+    fake_latency.AddLatencyNumberWithTimestamp(
+        ui::INPUT_EVENT_LATENCY_ACK_RWH_COMPONENT, 0, 0,
+        base::TimeTicks() + base::TimeDelta::FromMilliseconds(timestamps_ms[2]),
+        1);
+
+    // Call ComputeInputLatencyHistograms directly to avoid OnInputEventAck
+    // overwriting components.
+    tracker()->ComputeInputLatencyHistograms(wheel_event.type(),
+                                             tracker()->latency_component_id(),
+                                             fake_latency, ack_state);
+
+    tracker()->OnInputEventAck(wheel_event, &latency, ack_state);
+  }
+
+  EXPECT_THAT(histogram_tester().GetAllSamples(
+                  "Event.Latency.QueueingTime.MouseWheelDefaultAllowed"),
+              ElementsAre(Bucket(14, 1)));
+}
+
 }  // namespace content