coinstats: add coins_count

Also changes existing CCoinsStats attributes to be C++11 initialized.

src/node/coinstats.cpp

@@ -38,6 +38,7 @@ static void ApplyStats(CCoinsStats &stats, CHashWriter& ss, const uint256& hash,
 //! Calculate statistics about the unspent transaction output set
 bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
 {
+    stats = CCoinsStats();
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
     assert(pcursor);
 
@@ -61,6 +62,7 @@ bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats)
             }
             prevkey = key.hash;
             outputs[key.n] = std::move(coin);
+            stats.coins_count++;
         } else {
             return error("%s: unable to read value", __func__);
         }

src/node/coinstats.h

@@ -15,16 +15,17 @@ class CCoinsView;
 
 struct CCoinsStats
 {
-    int nHeight;
-    uint256 hashBlock;
-    uint64_t nTransactions;
-    uint64_t nTransactionOutputs;
-    uint64_t nBogoSize;
-    uint256 hashSerialized;
-    uint64_t nDiskSize;
-    CAmount nTotalAmount;
-
-    CCoinsStats() : nHeight(0), nTransactions(0), nTransactionOutputs(0), nBogoSize(0), nDiskSize(0), nTotalAmount(0) {}
+    int nHeight{0};
+    uint256 hashBlock{};
+    uint64_t nTransactions{0};
+    uint64_t nTransactionOutputs{0};
+    uint64_t nBogoSize{0};
+    uint256 hashSerialized{};
+    uint64_t nDiskSize{0};
+    CAmount nTotalAmount{0};
+
+    //! The number of coins contained.
+    uint64_t coins_count{0};
 };
 
 //! Calculate statistics about the unspent transaction output set