[Chromecast] Set dummy metrics session ID for browser tests

chromecast/base/metrics/cast_metrics_helper.h

 // Copyright 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 CHROMECAST_BASE_METRICS_CAST_METRICS_HELPER_H_
 #define CHROMECAST_BASE_METRICS_CAST_METRICS_HELPER_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 86 matching lines @@
   // events internally unless SetMetricsSink(NULL) is called.
   // CastMetricsHelper can only hold one MetricsSink instance.
   // Caller retains ownership of MetricsSink.
   virtual void SetMetricsSink(MetricsSink* delegate);
 
   // Sets a default callback to record user action when MetricsSink is not set.
   // This function could be called multiple times (in unittests), and
   // CastMetricsHelper only honors the last one.
   virtual void SetRecordActionCallback(const RecordActionCallback& callback);
 
+  // Sets an all-0's session ID for running browser tests.
+  void SetDummySessionIdForTesting();
+
  protected:
   // Creates a CastMetricsHelper instance with no task runner. This should only
   // be used by tests, since invoking any non-overridden methods on this
   // instance will cause a failure.
   CastMetricsHelper();
 
  private:
   static std::string EncodeAppInfoIntoMetricsName(
       const std::string& action_name,
       const std::string& app_id,
@@ skipping 27 matching lines @@
   // Default RecordAction callback when metrics_sink_ is not set.
   RecordActionCallback record_action_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(CastMetricsHelper);
 };
 
 }  // namespace metrics
 }  // namespace chromecast
 
 #endif  // CHROMECAST_BASE_METRICS_CAST_METRICS_HELPER_H_