Remove old prefetcher histogram code in render_frame_impl

content/public/renderer/document_state.h

Index: content/public/renderer/document_state.h
diff --git a/content/public/renderer/document_state.h b/content/public/renderer/document_state.h
index bc772691f34f1be02aeb7d8b968d801be8c6e0cd..437cec09eef4773e926b92a0486036e6740262b5 100644
--- a/content/public/renderer/document_state.h
+++ b/content/public/renderer/document_state.h
@@ -167,20 +167,6 @@ class CONTENT_EXPORT DocumentState
     proxy_server_ = proxy_server;
   }
 
-  void set_was_prefetcher(bool value) { was_prefetcher_ = value; }
-  bool was_prefetcher() const { return was_prefetcher_; }
-
-  void set_was_referred_by_prefetcher(bool value) {
-    was_referred_by_prefetcher_ = value;
-  }
-  bool was_referred_by_prefetcher() const {
-    return was_referred_by_prefetcher_;
-  }
-
-  void set_was_after_preconnect_request(bool value) {
-    was_after_preconnect_request_ = value;
-  }
-  bool was_after_preconnect_request() { return was_after_preconnect_request_; }
 
   // For LoadDataWithBaseURL navigations, |was_load_data_with_base_url_request_|
   // is set to true and |data_url_| is set to the data URL of the navigation.
@@ -229,11 +215,6 @@ class CONTENT_EXPORT DocumentState
   bool was_fetched_via_proxy_;
   net::HostPortPair proxy_server_;
 
-  // A prefetcher is a page that contains link rel=prefetch elements.
-  bool was_prefetcher_;
-  bool was_referred_by_prefetcher_;
-  bool was_after_preconnect_request_;
-
   bool was_load_data_with_base_url_request_;
   GURL data_url_;