Use more flexible field trial control on resource prefetching for mobile web

chrome/browser/predictors/resource_prefetch_predictor.cc

 // 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.
 
 #include "chrome/browser/predictors/resource_prefetch_predictor.h"
 
 #include <map>
 #include <set>
 #include <utility>
 
@@ skipping 294 matching lines @@
     : profile_(profile),
       config_(config),
       initialization_state_(NOT_INITIALIZED),
       tables_(PredictorDatabaseFactory::GetForProfile(
           profile)->resource_prefetch_tables()),
       results_map_deleter_(&results_map_) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   // Some form of learning has to be enabled.
   DCHECK(config_.IsLearningEnabled());
-  if (config_.IsURLPrefetchingEnabled())
+  if (config_.IsURLPrefetchingEnabled(profile_))
     DCHECK(config_.IsURLLearningEnabled());
-  if (config_.IsHostPrefetchingEnabled())
+  if (config_.IsHostPrefetchingEnabled(profile_))
     DCHECK(config_.IsHostLearningEnabled());
 }
 
 ResourcePrefetchPredictor::~ResourcePrefetchPredictor() {
 }
 
 void ResourcePrefetchPredictor::RecordURLRequest(
     const URLRequestSummary& request) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   if (initialization_state_ != INITIALIZED)
@@ skipping 242 matching lines @@
 bool ResourcePrefetchPredictor::GetPrefetchData(
     const NavigationID& navigation_id,
     ResourcePrefetcher::RequestVector* prefetch_requests,
     PrefetchKeyType* key_type) {
   DCHECK(prefetch_requests);
   DCHECK(key_type);
 
   *key_type = PREFETCH_KEY_TYPE_URL;
   const GURL& main_frame_url = navigation_id.main_frame_url;
 
-  bool use_url_data = config_.IsPrefetchingEnabled() ?
-      config_.IsURLPrefetchingEnabled() : config_.IsURLLearningEnabled();
+  bool use_url_data = config_.IsPrefetchingEnabled(profile_) ?
+      config_.IsURLPrefetchingEnabled(profile_) :
+      config_.IsURLLearningEnabled();
   if (use_url_data) {
     PrefetchDataMap::const_iterator iterator =
         url_table_cache_->find(main_frame_url.spec());
     if (iterator != url_table_cache_->end())
       PopulatePrefetcherRequest(iterator->second, prefetch_requests);
   }
   if (!prefetch_requests->empty())
     return true;
 
-  bool use_host_data = config_.IsPrefetchingEnabled() ?
-      config_.IsHostPrefetchingEnabled() : config_.IsHostLearningEnabled();
+  bool use_host_data = config_.IsPrefetchingEnabled(profile_) ?
+      config_.IsHostPrefetchingEnabled(profile_) :
+      config_.IsHostLearningEnabled();
   if (use_host_data) {
     PrefetchDataMap::const_iterator iterator =
         host_table_cache_->find(main_frame_url.host());
     if (iterator != host_table_cache_->end()) {
       *key_type = PREFETCH_KEY_TYPE_HOST;
       PopulatePrefetcherRequest(iterator->second, prefetch_requests);
     }
   }
 
   return !prefetch_requests->empty();
@@ skipping 102 matching lines @@
 
 void ResourcePrefetchPredictor::OnHistoryAndCacheLoaded() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   DCHECK_EQ(initialization_state_, INITIALIZING);
 
   notification_registrar_.Add(this,
                               chrome::NOTIFICATION_HISTORY_URLS_DELETED,
                               content::Source<Profile>(profile_));
 
   // Initialize the prefetch manager only if prefetching is enabled.
-  if (config_.IsPrefetchingEnabled()) {
+  if (config_.IsPrefetchingEnabled(profile_)) {
     prefetch_manager_ = new ResourcePrefetcherManager(
         this, config_, profile_->GetRequestContext());
   }
 
   initialization_state_ = INITIALIZED;
 }
 
 void ResourcePrefetchPredictor::CleanupAbandonedNavigations(
     const NavigationID& navigation_id) {
   static const base::TimeDelta max_navigation_age =
@@ skipping 487 matching lines @@
     RPP_PREDICTED_HISTOGRAM_PERCENTAGE(
         "PrefetchFromNetworkPercentOfTotalFromNetwork",
         prefetch_network * 100.0 / total_resources_fetched_from_network);
   }
 
 #undef RPP_PREDICTED_HISTOGRAM_PERCENTAGE
 #undef RPP_PREDICTED_HISTOGRAM_COUNTS
 }
 
 }  // namespace predictors