GRC: Added Tab coordination units behind a feature flag

chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.cc

Index: chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.cc
diff --git a/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.cc b/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cfa88b7309c048992a75f07789e094e8cff35c8b
--- /dev/null
+++ b/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.cc
@@ -0,0 +1,37 @@
+// 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.
+
+#include "chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h"
+
+#include "content/public/common/service_manager_connection.h"
+#include "services/resource_coordinator/public/cpp/resource_coordinator_features.h"
+
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(ResourceCoordinatorWebContentsObserver);
+
+ResourceCoordinatorWebContentsObserver::ResourceCoordinatorWebContentsObserver(
+    content::WebContents* web_contents)
+    : WebContentsObserver(web_contents) {
+  tab_resource_coordinator_ =
+      base::MakeUnique<resource_coordinator::ResourceCoordinatorInterface>(
+          content::ServiceManagerConnection::GetForProcess()->GetConnector(),
+          resource_coordinator::CoordinationUnitType::kWebContents);
+}
+
+ResourceCoordinatorWebContentsObserver::
+    ~ResourceCoordinatorWebContentsObserver() = default;
+
+// static
+bool ResourceCoordinatorWebContentsObserver::IsEnabled() {
+  return base::FeatureList::IsEnabled(features::kGlobalResourceCoordinator);
+}
+
+void ResourceCoordinatorWebContentsObserver::WasShown() {
+  tab_resource_coordinator_->SendEvent(
+      resource_coordinator::EventType::kOnWebContentsShown);
+}
+
+void ResourceCoordinatorWebContentsObserver::WasHidden() {
+  tab_resource_coordinator_->SendEvent(
+      resource_coordinator::EventType::kOnWebContentsHidden);
+}