Reduce cs_main lock accumulation during GUI startup

src/qt/bitcoin.h

@@ -12,6 +12,8 @@
 #include <QApplication>
 #include <memory>
 
+#include <interfaces/node.h>
+
 class BitcoinGUI;
 class ClientModel;
 class NetworkStyle;
@@ -21,10 +23,6 @@ class PlatformStyle;
 class WalletController;
 class WalletModel;
 
-namespace interfaces {
-class Handler;
-class Node;
-} // namespace interfaces
 
 /** Class encapsulating Bitcoin Core startup and shutdown.
  * Allows running startup and shutdown in a different thread from the UI thread.
@@ -40,7 +38,7 @@ public Q_SLOTS:
     void shutdown();
 
 Q_SIGNALS:
-    void initializeResult(bool success);
+    void initializeResult(bool success, interfaces::BlockAndHeaderTipInfo tip_info);
     void shutdownResult();
     void runawayException(const QString &message);
 
@@ -91,7 +89,7 @@ public:
     void setupPlatformStyle();
 
 public Q_SLOTS:
-    void initializeResult(bool success);
+    void initializeResult(bool success, interfaces::BlockAndHeaderTipInfo tip_info);
     void shutdownResult();
     /// Handle runaway exceptions. Shows a message box with the problem and quits the program.
     void handleRunawayException(const QString &message);