--- a/toolkit/components/telemetry/TelemetryHistogram.cpp
+++ b/toolkit/components/telemetry/TelemetryHistogram.cpp
@@ -869,17 +869,16 @@ namespace {
 class KeyedHistogram {
 public:
   KeyedHistogram(const nsACString &name, const nsACString &expiration,
                  uint32_t histogramType, uint32_t min, uint32_t max,
                  uint32_t bucketCount, uint32_t dataset);
   nsresult GetHistogram(const nsCString& name, Histogram** histogram, bool subsession);
   Histogram* GetHistogram(const nsCString& name, bool subsession);
   uint32_t GetHistogramType() const { return mHistogramType; }
-  nsresult GetDataset(uint32_t* dataset) const;
   nsresult GetJSKeys(JSContext* cx, JS::CallArgs& args);
   nsresult GetJSSnapshot(JSContext* cx, JS::Handle<JSObject*> obj,
                          bool subsession, bool clearSubsession);
 
   void SetRecordingEnabled(bool aEnabled) { mRecordingEnabled = aEnabled; };
   bool IsRecordingEnabled() const { return mRecordingEnabled; };
 
   nsresult Add(const nsCString& key, uint32_t aSample);
@@ -980,24 +979,16 @@ KeyedHistogram::GetHistogram(const nsCSt
   Histogram* h = nullptr;
   if (NS_FAILED(GetHistogram(key, &h, subsession))) {
     return nullptr;
   }
   return h;
 }
 
 nsresult
-KeyedHistogram::GetDataset(uint32_t* dataset) const
-{
-  MOZ_ASSERT(dataset);
-  *dataset = mDataset;
-  return NS_OK;
-}
-
-nsresult
 KeyedHistogram::Add(const nsCString& key, uint32_t sample)
 {
   bool canRecordDataset = CanRecordDataset(mDataset,
                                            internal_CanRecordBase(),
                                            internal_CanRecordExtended());
   if (!canRecordDataset) {
     return NS_OK;
   }