Change multi-prerender API to include per launcher slots.

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/metrics/field_trial.h"
@@ skipping 150 matching lines @@
 
 void PrerenderHistograms::RecordPrerenderStarted(Origin origin) const {
   if (OriginIsOmnibox(origin)) {
     UMA_HISTOGRAM_ENUMERATION(
         StringPrintf("Prerender.OmniboxPrerenderCount%s",
                      PrerenderManager::GetModeString()), 1, 2);
   }
 }
 
 void PrerenderHistograms::RecordConcurrency(size_t prerender_count,
                                             size_t max_concurrency) const {

[mmenke, 2012/12/18 17:15:15]

Since there is no longer a real "max_concurrency", I think it's a little odd to
take it as an argument.

[gavinp, 2012/12/18 20:15:12]

But max_link_concurrency  is also used in here as a proxy for being on the multi
prerender experiment. So I've moved a test on that experiment into prerender
manager.

-  static const size_t kMaxRecordableConcurrency = 3;
+  static const size_t kMaxRecordableConcurrency = 20;
   DCHECK_GE(kMaxRecordableConcurrency, max_concurrency);
   if (max_concurrency > 1) {
     UMA_HISTOGRAM_ENUMERATION(
         StringPrintf("Prerender.PrerenderCountOf%" PRIuS "Max",
-                     max_concurrency),
+                     kMaxRecordableConcurrency),
         prerender_count, kMaxRecordableConcurrency + 1);
   }
 }
 
 void PrerenderHistograms::RecordUsedPrerender(Origin origin) const {
   if (OriginIsOmnibox(origin)) {
     UMA_HISTOGRAM_ENUMERATION(
         StringPrintf("Prerender.OmniboxNavigationsUsedPrerenderCount%s",
                      PrerenderManager::GetModeString()), 1, 2);
   }
@@ skipping 202 matching lines @@
   return last_experiment_id_;
 }
 
 bool PrerenderHistograms::IsOriginExperimentWash() const {
   if (!WithinWindow())
     return false;
   return origin_experiment_wash_;
 }
 
 }  // namespace prerender