refactor: Move RPCNotifyBlockChange out of `rpc/server.h`

src/init.cpp

@@ -27,6 +27,7 @@
 #include "policy/policy.h"
 #include "rpc/server.h"
 #include "rpc/register.h"
+#include "rpc/blockchain.h"
 #include "script/standard.h"
 #include "script/sigcache.h"
 #include "scheduler.h"

src/rpc/blockchain.h

@@ -16,5 +16,8 @@ class CBlockIndex;
  */
 double GetDifficulty(const CBlockIndex* blockindex = nullptr);
 
+/** Callback for when block tip changed. */
+void RPCNotifyBlockChange(bool ibd, const CBlockIndex *);
+
 #endif
 

src/rpc/server.h

@@ -198,7 +198,6 @@ bool StartRPC();
 void InterruptRPC();
 void StopRPC();
 std::string JSONRPCExecBatch(const UniValue& vReq);
-void RPCNotifyBlockChange(bool ibd, const CBlockIndex *);
 
 // Retrieves any serialization flags requested in command line argument
 int RPCSerializationFlags();