Get network resource usage from ChromeResourceDispatcherHostDelegate

chrome/browser/offline_pages/background_loader_offliner.cc

 // Copyright 2016 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.
 
 #include "chrome/browser/offline_pages/background_loader_offliner.h"
 
 #include "base/bind.h"
 #include "base/json/json_writer.h"
 #include "base/metrics/histogram_functions.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 88 matching lines @@
     std::unique_ptr<LoadTerminationListener> load_termination_listener)
     : browser_context_(browser_context),
       offline_page_model_(offline_page_model),
       policy_(policy),
       load_termination_listener_(std::move(load_termination_listener)),
       save_state_(NONE),
       page_load_state_(SUCCESS),
       network_bytes_(0LL),
       is_low_bar_met_(false),
       did_snapshot_on_last_retry_(false),
+      started_count_(0LL),
+      completed_count_(0LL),
       weak_ptr_factory_(this) {
   DCHECK(offline_page_model_);
   DCHECK(browser_context_);
   load_termination_listener_->set_offliner(this);
 }
 
 BackgroundLoaderOffliner::~BackgroundLoaderOffliner() {}
 
 // static
 BackgroundLoaderOffliner* BackgroundLoaderOffliner::FromWebContents(
@@ skipping 222 matching lines @@
   RecordOffliningPreviewsUMA(pending_request_->client_id(), navigation_data);
 }
 
 void BackgroundLoaderOffliner::SetSnapshotControllerForTest(
     std::unique_ptr<SnapshotController> controller) {
   snapshot_controller_ = std::move(controller);
 }
 void BackgroundLoaderOffliner::ObserveResourceLoading(
     ResourceLoadingObserver::ResourceDataType type,
     bool started) {
-  // TODO(petewil) Not implemented yet.
-  return;
+  // TODO(petewil): Use actual signal type instead of hardcoding name to
+  // image.
+  // Add the signal to extra data, and use for tracking.
+  if (type == ResourceDataType::IMAGE) {
+    if (started) {
+      started_count_++;
+      signal_data_.SetDouble("StartedImages", started_count_);
+    } else {
+      completed_count_++;
+      signal_data_.SetDouble("CompletedImages", completed_count_);
+    }
+  }
 }
 
 void BackgroundLoaderOffliner::OnNetworkBytesChanged(int64_t bytes) {
   if (pending_request_ && save_state_ != SAVING) {
     network_bytes_ += bytes;
     progress_callback_.Run(*pending_request_, network_bytes_);
   }
 }
 
 void BackgroundLoaderOffliner::StartSnapshot() {
@@ skipping 153 matching lines @@
   base::TimeDelta delay_so_far = current_time - load_start_time_;
   // We would prefer to use int64_t here, but JSON does not support that type.
   // Given the choice between int and double, we choose to implicitly convert to
   // a double since it maintains more precision (we can get a longer time in
   // milliseconds than we can with a 2 bit int, 53 bits vs 32).
   double delay = delay_so_far.InMilliseconds();
   signal_data_.SetDouble(signal_name, delay);
 }
 
 }  // namespace offline_pages