Histogram the amount of time spent on HTTP(S) page loads

chrome/browser/page_load_metrics/observers/https_engagement_page_load_metrics_observer.cc

Index: chrome/browser/page_load_metrics/observers/https_engagement_page_load_metrics_observer.cc
diff --git a/chrome/browser/page_load_metrics/observers/https_engagement_page_load_metrics_observer.cc b/chrome/browser/page_load_metrics/observers/https_engagement_page_load_metrics_observer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1eba05b461a9a4a5e29676264ed5ef587e090ee8
--- /dev/null
+++ b/chrome/browser/page_load_metrics/observers/https_engagement_page_load_metrics_observer.cc
@@ -0,0 +1,59 @@
+// 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/page_load_metrics/observers/https_engagement_page_load_metrics_observer.h"
+
+#include "base/metrics/histogram_macros.h"
+#include "url/url_constants.h"
+
+namespace internal {
+const char kHttpsEngagementHistogram[] = "Navigation.EngagementTime.HTTPS";
+const char kHttpEngagementHistogram[] = "Navigation.EngagementTime.HTTP";
+}
+
+HttpsEngagementPageLoadMetricsObserver::HttpsEngagementPageLoadMetricsObserver()
+    : currently_in_foreground_(false) {}
+
+void HttpsEngagementPageLoadMetricsObserver::OnStart(
+    content::NavigationHandle* navigation_handle,
+    const GURL& currently_committed_url,
+    bool started_in_foreground) {
+  if (started_in_foreground)
+    OnShown();
+}
+
+void HttpsEngagementPageLoadMetricsObserver::OnHidden() {
+  if (!currently_in_foreground_)
+    return;
+  foreground_time_ += base::TimeTicks::Now() - last_time_shown_;
+  currently_in_foreground_ = false;
+}
+
+void HttpsEngagementPageLoadMetricsObserver::OnShown() {
+  last_time_shown_ = base::TimeTicks::Now();
+  currently_in_foreground_ = true;
+}
+
+void HttpsEngagementPageLoadMetricsObserver::OnComplete(
+    const page_load_metrics::PageLoadTiming& timing,
+    const page_load_metrics::PageLoadExtraInfo& extra_info) {
+  if (!extra_info.committed_url.is_valid() ||
+      extra_info.time_to_commit.is_zero())
+    return;
+
+  // Don't record anything if the user never saw it.
+  if (!currently_in_foreground_ && foreground_time_.is_zero())
+    return;
+
+  if (currently_in_foreground_)
+    OnHidden();
+
+  if (extra_info.committed_url.SchemeIs(url::kHttpsScheme)) {
+    UMA_HISTOGRAM_LONG_TIMES_100(internal::kHttpsEngagementHistogram,
+                                 foreground_time_);
+  } else if (extra_info.committed_url.SchemeIs(url::kHttpScheme)) {
+    UMA_HISTOGRAM_LONG_TIMES_100(internal::kHttpEngagementHistogram,
+                                 foreground_time_);
+  }
+}