[PageLoadMetrics] Keep track of Ad Sizes on Pages

chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h

+// Copyright 2017 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.
+
+#ifndef CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ADS_PAGE_LOAD_METRICS_OBSERVER_H_
+#define CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ADS_PAGE_LOAD_METRICS_OBSERVER_H_
+
+#include <list>
+#include <unordered_map>
+
+#include "base/macros.h"
+#include "chrome/browser/page_load_metrics/page_load_metrics_observer.h"
+#include "net/http/http_response_info.h"
+
+class AdsPageLoadMetricsObserver
+    : public page_load_metrics::PageLoadMetricsObserver {
+ public:
+  AdsPageLoadMetricsObserver();
+  ~AdsPageLoadMetricsObserver() override;
+
+  // page_load_metrics::PageLoadMetricsObserver:s
+  ObservePolicy OnCommit(content::NavigationHandle* navigation_handle) override;
+  ObservePolicy OnCommitSubFrame(
+      content::NavigationHandle* navigation_handle) override;
+  ObservePolicy FlushMetricsOnAppEnterBackground(
+      const page_load_metrics::PageLoadTiming& timing,
+      const page_load_metrics::PageLoadExtraInfo& extra_info) override;
+  void OnLoadedResource(
+      const page_load_metrics::ExtraRequestInfo& extra_request_info) override;
+  void OnComplete(const page_load_metrics::PageLoadTiming& timing,
+                  const page_load_metrics::PageLoadExtraInfo& info) override;
+
+ private:
+  struct AdFrameData {
+    size_t frame_bytes;
+    size_t frame_bytes_uncached;
+  };
+
+  using FrameTreeNodeId = int;
+
+  friend class AdsPageLoadMetricsObserverTest;
+
+  void RecordHistograms();
+  AdFrameData* FindAdAncestor(content::NavigationHandle* navigation_handle);
+
+  // Checks to see if a resource is waiting for |frame_tree_node_id| to commit
+  // before it can be processed. If so, call OnLoadedResource for the delayed
+  // resource.
+  void ProcessDelayedResources(FrameTreeNodeId frame_tree_node_id);
+
+  // Stores the size data of each ad frame. Pointed to by ad_frames_ so use a
+  // data structure that won't move the data around.
+  std::list<AdFrameData> ad_frames_data_storage_;

[Charlie Harrison, 2017/04/11 17:30:06]

It is append-only. Why not use std::vector?

[jkarlin, 2017/04/13 17:25:30]

Because I'm taking pointers to its elements. When vectors grow they copy the
elements to a new vector of larger size.

+
+  // Maps a frame (by id) to the AdFraneData responsible for the frame. The

[Charlie Harrison, 2017/04/11 17:30:06]

s/AdFraneData/AdFrameData

[jkarlin, 2017/04/13 17:25:30]

Done.

+  // responsible frame is the top-most frame labeled as an ad in the frame's
+  // ancestry, which may be itself. If no responsible frame is found, the data
+  // is nullptr.
+  std::unordered_map<FrameTreeNodeId, AdFrameData*> ad_frames_data_;
+
+  // When the observer receives report of a document resource loading for a
+  // sub-frame before the sub-frame commit occurs, hold onto the resource
+  // request info (delay it) until the sub-frame commits.
+  std::unordered_map<FrameTreeNodeId, page_load_metrics::ExtraRequestInfo>
+      delayed_resources_;
+
+  size_t page_bytes_ = 0;
+  size_t uncached_page_bytes_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(AdsPageLoadMetricsObserver);
+};
+
+#endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ADS_PAGE_LOAD_METRICS_OBSERVER_H_