Reduce Cache.h includes further via one forward declaration

src/Cache.cpp

@@ -104,7 +104,6 @@ numeric_key_comparison(const MDB_val *a, const MDB_val *b)
         return -1;
 }
 
-
 Cache::Cache(const QString &userId, QObject *parent)
   : QObject{parent}
   , env_{nullptr}
@@ -2901,4 +2900,3 @@ restoreSessions()
         return instance_->restoreSessions();
 }
 } // namespace cache
-

src/ChatPage.h

@@ -22,6 +22,7 @@
 #include <variant>
 
 #include <mtx/common.hpp>
+#include <mtx/requests.hpp>
 #include <mtx/responses.hpp>
 #include <mtxclient/http/errors.hpp>
 

src/MainWindow.cpp

@@ -23,6 +23,7 @@
 
 #include <mtx/requests.hpp>
 
+#include "Cache.h"
 #include "ChatPage.h"
 #include "Config.h"
 #include "Logging.h"

src/MxcImageProvider.cpp

@@ -1,8 +1,8 @@
 #include "MxcImageProvider.h"
 
 #include "Cache.h"
-#include "MatrixClient.h"
 #include "Logging.h"
+#include "MatrixClient.h"
 
 void
 MxcImageResponse::run()

src/QuickSwitcher.cpp

@@ -22,6 +22,7 @@
 #include <QTimer>
 #include <QtConcurrent>
 
+#include "Cache.h"
 #include "QuickSwitcher.h"
 #include "popups/SuggestionsPopup.h"
 

src/UserSettingsPage.cpp

@@ -29,6 +29,7 @@
 #include <QString>
 #include <QTextStream>
 
+#include "Cache.h"
 #include "Config.h"
 #include "MatrixClient.h"
 #include "Olm.h"

src/Utils.cpp

@@ -15,6 +15,7 @@
 
 #include <cmark.h>
 
+#include "Cache.h"
 #include "Config.h"
 
 using TimelineEvent = mtx::events::collections::TimelineEvents;

src/Utils.h

@@ -2,7 +2,6 @@
 
 #include <variant>
 
-#include "Cache.h"
 #include "RoomInfoListItem.h"
 
 #include <QCoreApplication>
@@ -13,6 +12,12 @@
 
 #include <qmath.h>
 
+namespace cache {
+// Forward declarations to prevent dependency on Cache.h, since this header is included often!
+QString
+displayName(const QString &room_id, const QString &user_id);
+}
+
 class QComboBox;
 
 // Contains information about related events for

src/dialogs/RoomSettings.cpp

@@ -16,6 +16,7 @@
 
 #include "dialogs/RoomSettings.h"
 
+#include "Cache.h"
 #include "ChatPage.h"
 #include "Config.h"
 #include "Logging.h"