interfaces, refactor: Add more block information to block connected notifications

Add new interfaces::BlockInfo struct to be able to pass extra block
information (file and undo information) to indexes which they are
updated to use high level interfaces::Chain notifications.

This commit does not change behavior in any way.

src/interfaces/chain.h

@@ -18,6 +18,7 @@
 
 class ArgsManager;
 class CBlock;
+class CBlockUndo;
 class CFeeRate;
 class CRPCCommand;
 class CScheduler;
@@ -67,6 +68,19 @@ public:
     mutable bool found = false;
 };
 
+//! Block data sent with blockConnected, blockDisconnected notifications.
+struct BlockInfo {
+    const uint256& hash;
+    const uint256* prev_hash = nullptr;
+    int height = -1;
+    int file_number = -1;
+    unsigned data_pos = 0;
+    const CBlock* data = nullptr;
+    const CBlockUndo* undo_data = nullptr;
+
+    BlockInfo(const uint256& hash LIFETIMEBOUND) : hash(hash) {}
+};
+
 //! Interface giving clients (wallet processes, maybe other analysis tools in
 //! the future) ability to access to the chain state, receive notifications,
 //! estimate fees, and submit transactions.
@@ -239,8 +253,8 @@ public:
         virtual ~Notifications() {}
         virtual void transactionAddedToMempool(const CTransactionRef& tx, uint64_t mempool_sequence) {}
         virtual void transactionRemovedFromMempool(const CTransactionRef& tx, MemPoolRemovalReason reason, uint64_t mempool_sequence) {}
-        virtual void blockConnected(const CBlock& block, int height) {}
-        virtual void blockDisconnected(const CBlock& block, int height) {}
+        virtual void blockConnected(const BlockInfo& block) {}
+        virtual void blockDisconnected(const BlockInfo& block) {}
         virtual void updatedBlockTip() {}
         virtual void chainStateFlushed(const CBlockLocator& locator) {}
     };