Speculatively launch Service Workers on mouse/touch events. [4/5]

content/browser/service_worker/service_worker_metrics.cc

Index: content/browser/service_worker/service_worker_metrics.cc
diff --git a/content/browser/service_worker/service_worker_metrics.cc b/content/browser/service_worker/service_worker_metrics.cc
index 0c1cfca0951b5642261ca5dac6621c4b368e8a3d..98d494384abb69ed02d37c48be498d951b932600 100644
--- a/content/browser/service_worker/service_worker_metrics.cc
+++ b/content/browser/service_worker/service_worker_metrics.cc
@@ -213,6 +213,12 @@ const char* ServiceWorkerMetrics::EventTypeToString(EventType event_type) {
   return "error";
 }
 
+bool ServiceWorkerMetrics::IsNavigationHintEvent(EventType event_type) {
+  return event_type == EventType::NAVIGATION_HINT_LINK_MOUSE_DOWN ||
+         event_type == EventType::NAVIGATION_HINT_LINK_TAP_UNCONFIRMED ||
+         event_type == EventType::NAVIGATION_HINT_LINK_TAP_DOWN;
+}
+
 bool ServiceWorkerMetrics::ShouldExcludeSiteFromHistogram(Site site) {
   return site == ServiceWorkerMetrics::Site::NEW_TAB_PAGE;
 }
@@ -409,6 +415,34 @@ void ServiceWorkerMetrics::RecordEventHandledRatio(EventType event,
   }
 }
 
+void ServiceWorkerMetrics::RecordNavigationHintPrecision(
+    EventType start_worker_purpose,
+    bool frame_fetch_event_fired) {
+  DCHECK(IsNavigationHintEvent(start_worker_purpose));
+  UMA_HISTOGRAM_BOOLEAN("ServiceWorker.NavigationHintPrecision",
+                        frame_fetch_event_fired);
+  switch (start_worker_purpose) {
+    case EventType::NAVIGATION_HINT_LINK_MOUSE_DOWN:
+      UMA_HISTOGRAM_BOOLEAN(
+          "ServiceWorker.NavigationHintPrecision.LINK_MOUSE_DOWN",
+          frame_fetch_event_fired);
+      break;
+    case EventType::NAVIGATION_HINT_LINK_TAP_UNCONFIRMED:
+      UMA_HISTOGRAM_BOOLEAN(
+          "ServiceWorker.NavigationHintPrecision.LINK_TAP_UNCONFIRMED",
+          frame_fetch_event_fired);
+      break;
+    case EventType::NAVIGATION_HINT_LINK_TAP_DOWN:
+      UMA_HISTOGRAM_BOOLEAN(
+          "ServiceWorker.NavigationHintPrecision.LINK_TAP_DOWN",
+          frame_fetch_event_fired);
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
+}
+
 void ServiceWorkerMetrics::RecordEventTimeout(EventType event) {
   UMA_HISTOGRAM_ENUMERATION("ServiceWorker.RequestTimeouts.Count",
                             static_cast<int>(event),