[Prerender] first contentful paint histograms.

chrome/browser/prerender/prerender_histograms.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/prerender/prerender_histograms.h"
 
 #include <string>
 
 #include "base/format_macros.h"
 #include "base/logging.h"
@@ skipping 292 matching lines @@
                      perceived_page_load_time);
         } else if (recorded_non_overlapping) {
           RECORD_PLT("PerceivedPLTFirstAfterMissNonOverlappingOnly",
                      perceived_page_load_time);
         }
       }
     }
   }
 }
 
+void PrerenderHistograms::RecordPerceivedFirstContentfulPaintTime(
+    Origin origin,
+    base::TimeDelta perceived_first_contentful_paint,
+    bool was_hidden) {
+  RecordHistogramTime(GetPerceivedFirstContentfulPaintHistogramName(
+                          origin, IsOriginWash(), was_hidden),
+                      base::TimeDelta::FromMilliseconds(10),
+                      base::TimeDelta::FromMinutes(2),
+                      perceived_first_contentful_paint, 50);
+}
+
+void PrerenderHistograms::RecordPerceivedFirstContentfulPaintStatus(
+    Origin origin,
+    bool successful,
+    bool was_hidden) {
+  RecordHistogramEnum(
+      GetHistogramName(origin, IsOriginWash(), "PerceivedTTFCPRecorded") +

[droger, 2016/11/24 13:03:43]

If we want to compare NoStatePrefetch vs Prerender vs Control using a UMA
experiment, we need to report all the TTFCP in a single histogram, and then use
Finch to compare.

So in practice I think we should merge this histogram and the
"NoStatePrefetchTTFCP" histograms.

Another option would be to keep these histograms if they have some value, and
add another one that would be the merge of all of them. This could then be done
in another CL.

+          FirstContentfulPaintHiddenName(was_hidden),
+      successful ? 1 : 0, 2);
+}
+
 void PrerenderHistograms::RecordPageLoadTimeNotSwappedIn(
     Origin origin,
     base::TimeDelta page_load_time,
     const GURL& url) const {
   // If the URL to be prerendered is not a http[s] URL, or is a Google URL,
   // do not record.
   if (!url.SchemeIsHTTPOrHTTPS() || IsGoogleDomain(url))
     return;
   RECORD_PLT("PrerenderNotSwappedInPLT", page_load_time);
 }
@@ skipping 122 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
 
   const int kMaxRedirectCount = 10;
   std::string histogram_base_name = base::StringPrintf(
       "NoStatePrefetch%sResourceRedirects", is_main_resource ? "Main" : "Sub");
   std::string histogram_name =
       GetHistogramName(origin, IsOriginWash(), histogram_base_name);
   RecordHistogramEnum(histogram_name, redirect_count, kMaxRedirectCount);
 }
 
-void PrerenderHistograms::RecordFirstContentfulPaint(
+void PrerenderHistograms::RecordNoStateFirstContentfulPaint(
     Origin origin,
     bool is_no_store,
     base::TimeDelta time,
     base::TimeDelta prefetch_age) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   if (!prefetch_age.is_zero()) {
     DCHECK_NE(origin, ORIGIN_NONE);
     RecordHistogramTime(GetHistogramName(origin, IsOriginWash(),
                                          "Prerender.NoStatePrefetchAge"),
                         base::TimeDelta::FromMilliseconds(10),
                         base::TimeDelta::FromMinutes(30), prefetch_age, 50);
   }
 
-  RecordHistogramTime(GetFirstContentfulPaintHistogramName(
+  RecordHistogramTime(GetNoStateFirstContentfulPaintHistogramName(
                           origin, IsOriginWash(), is_no_store, prefetch_age),
                       base::TimeDelta::FromMilliseconds(10),
                       base::TimeDelta::FromMinutes(2), time, 50);
 }
 
 bool PrerenderHistograms::IsOriginWash() const {
   if (!WithinWindow())
     return false;
   return origin_wash_;
 }
 
 // static
-std::string PrerenderHistograms::GetFirstContentfulPaintHistogramName(
+std::string PrerenderHistograms::GetNoStateFirstContentfulPaintHistogramName(
     Origin origin,
     bool is_wash,
     bool is_no_store,
     base::TimeDelta prefetch_age) {
   std::string histogram_base_name;
   if (prefetch_age.is_zero()) {
     histogram_base_name = "NoStatePrefetchTTFCP.Reference";
   } else {
     histogram_base_name = prefetch_age < base::TimeDelta::FromMinutes(
                                              net::HttpCache::kPrefetchReuseMins)
                               ? "NoStatePrefetchTTFCP.Warm"
                               : "NoStatePrefetchTTFCP.Cold";
   }
 
   histogram_base_name += is_no_store ? ".NoStore" : ".Cacheable";
   return GetHistogramName(origin, is_wash, histogram_base_name);
 }
 
+// static
+std::string PrerenderHistograms::GetPerceivedFirstContentfulPaintHistogramName(
+    Origin origin,
+    bool is_wash,
+    bool was_hidden) {
+  return GetHistogramName(origin, is_wash, "PerceivedTTFCP") +
+         FirstContentfulPaintHiddenName(was_hidden);
+}
+
+std::string PrerenderHistograms::FirstContentfulPaintHiddenName(
+    bool was_hidden) {
+  return was_hidden ? ".Hidden" : ".Visible";
+}
+
 }  // namespace prerender