customtabs: Send time to first contentful paint to the caller.

chrome/browser/page_load_metrics/observers/android_page_load_metrics_observer.h

+// 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.
+
+#ifndef CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ANDROID_PAGE_LOAD_METRICS_OBSERVER_H_
+#define CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ANDROID_PAGE_LOAD_METRICS_OBSERVER_H_
+
+#include <jni.h>
+
+#include "base/macros.h"
+#include "chrome/browser/page_load_metrics/page_load_metrics_observer.h"
+
+namespace content {
+class WebContents;
+}  // namespace content
+
+class GURL;
+
+/** Forwards page load metrics to the Java side on Android. */
+class AndroidPageLoadMetricsObserver
+    : public page_load_metrics::PageLoadMetricsObserver {
+ public:
+  explicit AndroidPageLoadMetricsObserver(content::WebContents* web_contents);
+
+  // page_load_metrics::PageLoadMetricsObserver:
+  void OnFirstContentfulPaint(
+      const page_load_metrics::PageLoadTiming& timing,
+      const page_load_metrics::PageLoadExtraInfo& extra_info) override;
+
+ private:
+  content::WebContents* web_contents_;
+
+  DISALLOW_COPY_AND_ASSIGN(AndroidPageLoadMetricsObserver);
+};
+
+bool RegisterPageLoadMetricsBindings(JNIEnv* env);
+
+#endif  // CHROME_BROWSER_PAGE_LOAD_METRICS_OBSERVERS_ANDROID_PAGE_LOAD_METRICS_OBSERVER_H_