Add page view analytics to Observatory

runtime/observatory/lib/src/app/analytics.dart

+// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of app;
+
+class Analytics {
+  static final _UA = 'UA-26406144-17';
+  static final _name = 'Observatory';
+  static final _version = '1.11';
+  static final _googleAnalytics = new AnalyticsHtml(_UA, _name, _version);
+
+  static initialize() {
+    // We only send screen views. This is allowed without user permission.
+    // Note, before flipping this to be true we need a UI to allow users to
+    // control this.
+    _googleAnalytics.optIn = false;
+  }
+
+  /// Called whenever an Observatory page is viewed.
+  static Future reportPageView(Uri uri) {
+    // The screen name is the uri's path. e.g. inspect, profile.
+    final screenName = uri.path;
+    return _googleAnalytics.sendScreenView(screenName);
+  }
+}