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

content/browser/service_worker/service_worker_metrics.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_METRICS_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_METRICS_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
@@ skipping 77 matching lines @@
     // GEOFENCING = 6,  // Obsolete
     // SERVICE_PORT_CONNECT = 7,  // Obsolete
     MESSAGE = 8,
     NOTIFICATION_CLOSE = 9,
     FETCH_MAIN_FRAME = 10,
     FETCH_SUB_FRAME = 11,
     FETCH_SHARED_WORKER = 12,
     FETCH_SUB_RESOURCE = 13,
     UNKNOWN = 14,  // Used when event type is not known.
     FOREIGN_FETCH = 15,
+    NAVIGATION_HINT_LINK_MOUSE_DOWN = 16,
+    NAVIGATION_HINT_LINK_TAP_UNCONFIRMED = 17,
+    NAVIGATION_HINT_LINK_TAP_DOWN = 18,
     // Add new events to record here.
     NUM_TYPES
   };
 
   // Used for UMA. Append only.
   enum class Site {
     OTHER,  // Obsolete
     NEW_TAB_PAGE,
     WITH_FETCH_HANDLER,
     WITHOUT_FETCH_HANDLER,
     NUM_TYPES
   };
 
   // Not used for UMA.
   enum class StartSituation {
     UNKNOWN,
     DURING_STARTUP,
     EXISTING_PROCESS,
     NEW_PROCESS
   };
 
   // Not used for UMA.
   enum class LoadSource { NETWORK, HTTP_CACHE, SERVICE_WORKER_STORAGE };
 
   // Converts an event type to a string. Used for tracing.
   static const char* EventTypeToString(EventType event_type);
 
+  // Returns true when the event is for a navigation hint.
+  static bool IsNavigationHintEvent(EventType event_type);
+
   // Excludes NTP scope from UMA for now as it tends to dominate the stats and
   // makes the results largely skewed. Some metrics don't follow this policy
   // and hence don't call this function.
   static bool ShouldExcludeSiteFromHistogram(Site site);
   static bool ShouldExcludeURLFromHistogram(const GURL& url);
 
   // Used for ServiceWorkerDiskCache.
   static void CountInitDiskCacheResult(bool result);
   static void CountReadResponseResult(ReadResponseResult result);
   static void CountWriteResponseResult(WriteResponseResult result);
@@ skipping 35 matching lines @@
   static void RecordActivateEventStatus(ServiceWorkerStatusCode status,
                                         bool is_shutdown);
   static void RecordInstallEventStatus(ServiceWorkerStatusCode status);
 
   // Records how much of dispatched events are handled while a Service
   // Worker is awake (i.e. after it is woken up until it gets stopped).
   static void RecordEventHandledRatio(EventType event,
                                       size_t handled_events,
                                       size_t fired_events);
 
+  // Records the precision of the speculative launch of Service Workers for
+  // each navigation hint type when the worker is stopped. If there was no
+  // event fetched to the worker, |event_fired| is false. This means that the
+  // speculative launch was meaningless.
+  static void RecordNavigationHintPrecision(EventType start_worker_purpose,
+                                            bool event_fired);
+
   // Records how often a dispatched event times out.
   static void RecordEventTimeout(EventType event);
 
   // Records the amount of time spent handling an event.
   static void RecordEventDuration(EventType event,
                                   base::TimeDelta time,
                                   bool was_handled);
 
   // Records the result of dispatching a fetch event to a service worker.
   static void RecordFetchEventStatus(bool is_main_resource,
@@ skipping 41 matching lines @@
   static void RecordStartStatusAfterFailure(int failure_count,
                                             ServiceWorkerStatusCode status);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(ServiceWorkerMetrics);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_METRICS_H_