Add UMA metrics for Android Chrome Google Search.

chrome/browser/google/google_search_counter_android.h

+// Copyright (c) 2014 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_GOOGLE_GOOGLE_SEARCH_COUNTER_ANDROID_H_
+#define CHROME_BROWSER_GOOGLE_GOOGLE_SEARCH_COUNTER_ANDROID_H_
+
+#include "base/macros.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+class Profile;
+
+// A listener for counting Google searches in Android Chrome from various search
+// access points. No actual search query content is observed. See
+// GoogleSearchMetrics for more details about these access points.
+class GoogleSearchCounterAndroid : content::NotificationObserver {
+ public:
+  explicit GoogleSearchCounterAndroid(Profile* profile);
+  virtual ~GoogleSearchCounterAndroid();
+
+ private:
+  void ProcessCommittedEntry(const content::NotificationSource& source,
+                             const content::NotificationDetails& details);
+
+  // content::NotificationObserver:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  Profile* profile_;
+  content::NotificationRegistrar registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(GoogleSearchCounterAndroid);
+};
+
+#endif  // CHROME_BROWSER_GOOGLE_GOOGLE_SEARCH_COUNTER_ANDROID_H_