Record UMA only when network quality is eligible for caching

net/nqe/network_quality_store.h

 // Copyright 2016 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 NET_NQE_NETWORK_QUALITY_STORE_H_
 #define NET_NQE_NETWORK_QUALITY_STORE_H_
 
 #include <map>
 
 #include "base/macros.h"
@@ skipping 49 matching lines @@
                nqe::internal::CachedNetworkQuality* cached_network_quality);
 
   // Adds and removes |observer| from the list of cache observers. The
   // observers are notified on the same thread on which it was added. Addition
   // and removal of the observer must happen on the same thread.
   void AddNetworkQualitiesCacheObserver(
       NetworkQualitiesCacheObserver* observer);
   void RemoveNetworkQualitiesCacheObserver(
       NetworkQualitiesCacheObserver* observer);
 
+  // Returns true if network quality for |network_id| can be cached.
+  bool EligibleForCaching(const NetworkID& network_id) const;
+
   // If |disable_offline_check| is set to true, the offline check is disabled
   // when storing the network quality.
   void DisableOfflineCheckForTesting(bool disable_offline_check);
 
  private:
   // Maximum size of the store that holds network quality estimates.
   // A smaller size may reduce the cache hit rate due to frequent evictions.
   // A larger size may affect performance.
   static const size_t kMaximumNetworkQualityCacheSize = 10;
 
@@ skipping 27 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(NetworkQualityStore);
 };
 
 }  // namespace internal
 
 }  // namespace nqe
 
 }  // namespace net
 
 #endif  // NET_NQE_NETWORK_QUALITY_STORE_H_