predictors: Mark before_first_contentful_paint for resources fetched before fcp.

chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h

Index: chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h
diff --git a/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h b/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h
index cb00c68cb5b0c8afec1348cb04ef081df1fa5f3b..f04575ee4f6e9e1a68b8b476114a9c576395e335 100644
--- a/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h
+++ b/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_RESOURCE_PREFETCH_PREDICTOR_PAGE_LOAD_METRICS_OBSERVER_H_
 
 #include "chrome/browser/page_load_metrics/page_load_metrics_observer.h"
+#include "chrome/browser/predictors/resource_prefetch_common.h"
 
 namespace content {
 class WebContents;
@@ -35,7 +36,8 @@ class ResourcePrefetchPredictorPageLoadMetricsObserver
   // Public for testing. Normally one should use CreateIfNeeded. Predictor must
   // outlive this observer.
   explicit ResourcePrefetchPredictorPageLoadMetricsObserver(
-      predictors::ResourcePrefetchPredictor* predictor);
+      predictors::ResourcePrefetchPredictor* predictor,
+      content::WebContents* web_contents);
 
   ~ResourcePrefetchPredictorPageLoadMetricsObserver() override;
 
@@ -55,6 +57,8 @@ class ResourcePrefetchPredictorPageLoadMetricsObserver
 
  private:
   predictors::ResourcePrefetchPredictor* predictor_;
+  content::WebContents* web_contents_;
+  bool record_histograms_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourcePrefetchPredictorPageLoadMetricsObserver);
 };