ui: Cleanup class/struct forward declarations

chrome/browser/predictors/predictor_database.cc

Index: chrome/browser/predictors/predictor_database.cc
diff --git a/chrome/browser/predictors/predictor_database.cc b/chrome/browser/predictors/predictor_database.cc
index 81aca016221655535c1d81dff2d38fda5042a79f..04c4919f0c10c344a71755829712867bef54ba6f 100644
--- a/chrome/browser/predictors/predictor_database.cc
+++ b/chrome/browser/predictors/predictor_database.cc
@@ -73,9 +73,8 @@ PredictorDatabaseInternal::PredictorDatabaseInternal(Profile* profile)
       resource_prefetch_tables_(new ResourcePrefetchPredictorTables()) {
   db_->set_histogram_tag("Predictor");
 
-  // TODO(shess): The current mitigation for http://crbug.com/537742 stores
-  // state in the meta table, which this database does not use.
-  db_->set_mmap_disabled();
+  // This db does not use [meta] table, store mmap status data elsewhere.
+  db_->set_mmap_alt_status();
 
   ResourcePrefetchPredictorConfig config;
   is_resource_prefetch_predictor_enabled_ =