Add Keyboard Latency UMA Metrics.

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 8ebace902992f25699280254bcd8b17cf708a4a8..43cbf8224118d1ef885c960ea1ef9ca0b745d974 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
@@ -134,6 +134,8 @@ std::string LatencySourceEventTypeToInputModalityString(
       return "Wheel";
     case ui::SourceEventType::TOUCH:
       return "Touch";
+    case ui::SourceEventType::KEY:
+      return "Key";
     default:
       return "";
   }
@@ -190,7 +192,7 @@ void ComputeScrollLatencyHistograms(
   }
 }
 
-void ComputeTouchAndWheelScrollLatencyHistograms(
+void ComputeEndToEndLatencyHistograms(
     RenderWidgetHostDelegate* render_widget_host_delegate,
     const ui::LatencyInfo::LatencyComponent& gpu_swap_begin_component,
     const ui::LatencyInfo::LatencyComponent& gpu_swap_end_component,
@@ -246,6 +248,13 @@ void ComputeTouchAndWheelScrollLatencyHistograms(
           "Event.Latency.ScrollUpdate.Touch.TimeToScrollUpdateSwapBegin2",
           original_component, gpu_swap_begin_component);
     }
+  } else if (latency.FindLatency(ui::INPUT_EVENT_LATENCY_ORIGINAL_COMPONENT, 0,
+                                 &original_component)) {
+    if (input_modality == "Key") {
+      UMA_HISTOGRAM_INPUT_LATENCY_HIGH_RESOLUTION_MICROSECONDS(
+          "Event.Latency.EndToEnd.Key", original_component,
+          gpu_swap_begin_component);
+    }
   } else {
     // No original component found.
     return;
@@ -362,7 +371,8 @@ void RenderWidgetHostLatencyTracker::ComputeInputLatencyHistograms(
     return;
 
   if (type != blink::WebInputEvent::MouseWheel &&
-      !WebInputEvent::isTouchEventType(type)) {
+      !WebInputEvent::isTouchEventType(type) &&
+      !WebInputEvent::isKeyboardEventType(type)) {
     return;
   }
 
@@ -383,10 +393,12 @@ void RenderWidgetHostLatencyTracker::ComputeInputLatencyHistograms(
     if (type == blink::WebInputEvent::MouseWheel) {
       UMA_HISTOGRAM_CUSTOM_COUNTS("Event.Latency.Browser.WheelUI",
                                   ui_delta.InMicroseconds(), 1, 20000, 100);
-    } else {
-      DCHECK(WebInputEvent::isTouchEventType(type));
+    } else if (WebInputEvent::isTouchEventType(type)) {
       UMA_HISTOGRAM_CUSTOM_COUNTS("Event.Latency.Browser.TouchUI",
                                   ui_delta.InMicroseconds(), 1, 20000, 100);
+    } else if (WebInputEvent::isKeyboardEventType(type)) {

[mfomitchev, 2017/04/04 14:59:05]

Can we make this a DCHECK instead of an if?

[tdresser, 2017/05/01 15:49:21]

Added an else with NOTREACHED().

+      UMA_HISTOGRAM_CUSTOM_COUNTS("Event.Latency.Browser.KeyUI",
+                                  ui_delta.InMicroseconds(), 1, 20000, 50);
     }
   }
 
@@ -397,6 +409,8 @@ void RenderWidgetHostLatencyTracker::ComputeInputLatencyHistograms(
                           ack_result == INPUT_EVENT_ACK_STATE_CONSUMED;

[tdresser, 2017/05/01 15:49:21]

Ack, this is still broken in the non-touch case. I'll fix this in a followup
patch. (crbug.com/717017)

 
   std::string event_name = WebInputEvent::GetName(type);
+  if (WebInputEvent::isKeyboardEventType(type))
+    event_name = "KeyEvent";
 
   std::string default_action_status =
       action_prevented ? "DefaultPrevented" : "DefaultAllowed";
@@ -566,9 +580,11 @@ void RenderWidgetHostLatencyTracker::OnFrameSwapped(
   }
 
   ui::SourceEventType source_event_type = latency.source_event_type();
+
   if (source_event_type == ui::SourceEventType::WHEEL ||
-      source_event_type == ui::SourceEventType::TOUCH) {
-    ComputeTouchAndWheelScrollLatencyHistograms(
+      source_event_type == ui::SourceEventType::TOUCH ||
+      source_event_type == ui::SourceEventType::KEY) {
+    ComputeEndToEndLatencyHistograms(
         render_widget_host_delegate_, gpu_swap_begin_component,
         gpu_swap_end_component, latency_component_id_, latency);
   }