Create LoadingDataCollector class and have observers rely on it instead of ResourcePrefetchPredictor

chrome/browser/predictors/loading_predictor.h

Index: chrome/browser/predictors/loading_predictor.h
diff --git a/chrome/browser/predictors/loading_predictor.h b/chrome/browser/predictors/loading_predictor.h
index 9bcdd81fec861b45e1897c201c14f70d8aaced53..18eab7b059107bcc416c9b75c00b30c6f25eb1c7 100644
--- a/chrome/browser/predictors/loading_predictor.h
+++ b/chrome/browser/predictors/loading_predictor.h
@@ -8,6 +8,7 @@
 #include <memory>
 
 #include "base/memory/weak_ptr.h"
+#include "chrome/browser/predictors/loading_data_collector.h"
 #include "chrome/browser/predictors/resource_prefetch_common.h"
 #include "chrome/browser/predictors/resource_prefetch_predictor.h"
 #include "components/keyed_service/core/keyed_service.h"
@@ -44,12 +45,14 @@ class LoadingPredictor : public KeyedService,
 
   // Don't use, internal only.
   ResourcePrefetchPredictor* resource_prefetch_predictor() const;
+  LoadingDataCollector* loading_data_collector() const;
 
   // KeyedService:
   void Shutdown() override;
 
  private:
   std::unique_ptr<ResourcePrefetchPredictor> resource_prefetch_predictor_;
+  std::unique_ptr<LoadingDataCollector> loading_data_collector_;
 
   DISALLOW_COPY_AND_ASSIGN(LoadingPredictor);
 };