GRC: Added Tab coordination units behind a feature flag

chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h

Index: chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h
diff --git a/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h b/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h
new file mode 100644
index 0000000000000000000000000000000000000000..f8e9872f3a045d6d52e1e0116a50fc258d144284
--- /dev/null
+++ b/chrome/browser/resource_coordinator/resource_coordinator_web_contents_observer.h
@@ -0,0 +1,43 @@
+// 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_RESOURCE_COORDINATOR_RESOURCE_COORDINATOR_WEB_CONTENTS_OBSERVER_H_
+#define CHROME_BROWSER_RESOURCE_COORDINATOR_RESOURCE_COORDINATOR_WEB_CONTENTS_OBSERVER_H_
+
+#include "base/macros.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_user_data.h"
+#include "services/resource_coordinator/public/cpp/resource_coordinator_interface.h"
+
+class ResourceCoordinatorWebContentsObserver
+    : public content::WebContentsObserver,
+      public content::WebContentsUserData<
+          ResourceCoordinatorWebContentsObserver> {
+ public:
+  ~ResourceCoordinatorWebContentsObserver() override;
+
+  static bool IsEnabled();
+
+  resource_coordinator::ResourceCoordinatorInterface*
+  tab_resource_coordinator() {
+    return tab_resource_coordinator_.get();
+  }
+
+  // WebContentsObserver implementation.
+  void WasShown() override;
+  void WasHidden() override;
+
+ private:
+  explicit ResourceCoordinatorWebContentsObserver(
+      content::WebContents* web_contents);
+
+  friend class content::WebContentsUserData<
+      ResourceCoordinatorWebContentsObserver>;
+
+  std::unique_ptr<resource_coordinator::ResourceCoordinatorInterface>
+      tab_resource_coordinator_;
+  DISALLOW_COPY_AND_ASSIGN(ResourceCoordinatorWebContentsObserver);

[Lei Zhang, 2017/05/10 23:59:00]

nit: blank line above.

[oystein (OOO til 10th of July), 2017/05/11 22:52:47]

Done.

+};
+
+#endif  // CHROME_BROWSER_RESOURCE_COORDINATOR_RESOURCE_COORDINATOR_WEB_CONTENTS_OBSERVER_H_